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## #1 Help Me ! » Recursion and Special Sequences » 2015-11-16 06:18:42

lisathedork
Replies: 1

Hello, I need help with the following problems. I don't understand the information that my textbook provides.

1. Find the 4th term if the sequence in which a1 = 2 and a(n+1) = -4an + 2

2. Find the third iterate, x3, of the function f(x) = 3x + 5 for an initial value of x0 = 1

3. The rate of inflation is 3%. The cost of an item in future years can be found by iterating the function c(x) = 1.03x. Find the cost of a \$1500 refrigerator in three years if the rate of inflation remains consistant.

## #2 Re: Help Me ! » Arithmetic Sequence » 2015-11-15 15:05:50

Wow, I didn't know it was that easy!

Thank you so much for the help, I did the other problems with no trouble.

## #3 Help Me ! » Arithmetic Sequence » 2015-11-15 08:26:04

lisathedork
Replies: 4

Hello can someone help me with this one problem?

Given the Arithmetic sequence A1, A2, A3, A4

50, 60, 70, 80

What is the value of A29?

Can I get any notes on how to do this?

## #4 Re: Help Me ! » Area and Volume of Prisms and Pyramids » 2015-11-01 09:56:23

Thank you so much for the help! I'm now done with this math class.

## #5 Re: Help Me ! » Area and Volume of Prisms and Pyramids » 2015-10-28 04:29:37

I'm still having trouble with the following questions. Can someone please guide me through this?

For 1 through 10, what is the area and volume of the given shape, if the length of one side of the base is 6, the height is 8, and the slant height is 10?  (Not all shapes will require all three numbers.)

1. An equilateral triangle as the base.

This triangle just became the base of a regular prism, with a height of 8:
12. What is the lateral area?
13. What is the volume?
14. What is the area of the largest rectangular side?

This rectangle just became the base of a regular prism, with a height of 6:
17. What is the lateral area?
18. What is the total surface area?
19. What is the volume?
20. What is the area of the largest rectangular side?

## #6 Re: Help Me ! » Area and Volume of Prisms and Pyramids » 2015-10-20 12:58:56

Sorry for the late response!

I think this is the information you need.

For 1 through 10, what is the area and volume of the given shape, if the length of one side of the base is 6, the height is 8, and the slant height is 10?  (Not all shapes will require all three numbers.)
The shape is a right prism with -

## #7 Help Me ! » Area and Volume of Prisms and Pyramids » 2015-10-15 04:48:34

lisathedork
Replies: 9

Hello, I need help with the following questions.

The shape is a pyramid with:

6.  a rectangular base with a width of 4

7. a square base

8. a rectangular base with a width of 3

9. a rectangular base with a width of 5

10. a rectangular base with a width of 7

I have an isosceles triangle with a height of 4 and a base of 6:

11. What is the area?

This triangle just became the base of a regular prism, with a height of 8:

12. What is the lateral area?

13. What is the volume?

.

14. What is the area of the largest rectangular side?

I have a rectangle, with a length of 7 and a width of 4:

15. What is the perimeter?

16. What is the area?

This rectangle just became the base of a regular prism, with a height of 6:

17. What is the lateral area?

18. What is the total surface area?

19. What is the volume?

20. What is the area of the largest rectangular side?

## #8 Re: Help Me ! » Area of Circles and Sectors » 2015-09-29 08:50:02

Thank you so much for the help! I figure out how to do 14 & 15. Plus I made the minor changes in the other problems also. Yes, I wouldn't mind being called Lisa!

Thanks again!

## #9 Re: Help Me ! » Area of Circles and Sectors » 2015-09-28 06:24:57

What is the area of the circle of the radius is:
2.    SQRT(3)
A = (PI)r2
A = (PI)SQRT(3)2
A = 9 PI

What is the radius if the area of the circle is:
14. t^2(PI)
t2(PI) = (PI)r2
Need Help

15. t^2(PI)
t2(PI) = (PI)r2
Need help

What is the area of the sector if the radius is 6 and the degree measure is:

16.     26
A = (n/360)[(PI)r2]
A = (26/360)[(PI)62]
A = (13/180)[(PI)36]
A = 468/180(PI)
A = 2 3/5

20.    120
A = (n/360)[(PI)r2]
A = (120/360)[(PI)62]
A = (3/3)[(PI)36]
A = 108/3(PI)
A = 36

Sorry for the confusion!

## #10 Help Me ! » Area of Circles and Sectors » 2015-09-28 01:04:41

lisathedork
Replies: 4

May I get some assistance on these problems? Can you also give me some helpful notes also?

2. SQRT(3)
A = (PI)r^2
A = (PI)SQRT(3)^2
A = 9 PI

14. t^2(PI)
t2(PI) = (PI)r^2

15. t^2(PI)
t2(PI) = (PI)r^2

16. 26
A = (n/360)[^2]
A = (120/360)[(PI)62]
A = (3/3)[(PI)36]
A = 108/3(PI)
A = 36

20. 120
A = (n/360)[(PI)r^2]
A = (120/360)[(PI)62]
A = (3/3)[(PI)36]
A = 108/3(PI)
A = 36

## #11 Help Me ! » Geometric Probability » 2015-09-05 07:50:05

lisathedork
Replies: 1

The diameter of the black circle is 4 inches. The radius of the white middle circle is 6 inches and the Radius of the red circle is 9 inches.

1.    Robin knowns that if he hits the white part of the target, he just slightly win, therefore not embarrassing John. What is the probability that Robin will hit the white part of the target (not the red and not the bull’s-eye)? Show your work.

3.14(2)2
= 12.56

3.14(6)2
= 113.04

3.14(9)2
= 254.34

2.    After Robin shoots into the white area, John knows he cannot win, so he decides to set his sights on second place. To get second place, he needs to hit either the white circle or the bull’s-eye. What is the probability that he can do that? Show your work.

3.14(2)2 = 12.56 // 3.14(6)2 = 113.04 // 3.14(9)2 = 254.34

The table is 30 inches wide and 180 inches long. The width of the 2 and 3 rectangles is 12 inches. The sides of the 4 rectangle are 15 inches and the top and bottom are 12 inches. The 1 rectangle is twice as wide as the 2

3.    What are the dimensions of the 1 rectangle?
The dimensions of the 1 rectangle is

4.    What are the measurements of one of the 5 rectangles?
5.    You are playing shuffleboard in P.E. class. To score points, your disc must land in a box on the other side of the table and you are awarded the number of points that is in that box. What is the probability of scoring 1 point?
6.    What is the probability of scoring 2 points?
7.    What is the probability of scoring 3 points?
8.    What is the probability of scoring 4 point?
9.    What is the probability of scoring 5 point?
10.     What is the probability of scoring at all (any number of points)?

May I please get any helpful information on these problems? Anything is helpful.

## #12 Re: Help Me ! » Special Right Triangles » 2015-09-04 06:14:36

The help is no longer needed. I already figure the problems out, but thank you for the helpful information!

## #13 Help Me ! » Special Right Triangles » 2015-09-02 14:27:25

lisathedork
Replies: 3

May I please get some tips on how to do this? I thought I would get this but I'm having some trouble but thank you!

If you have a 45-45-90 triangle:

2. With a hypotenuse of SQRT(6), what is the length of one leg?

6. And one leg has a length of SQRT(8), what is the length of the hypotenuse?

7. And one leg has a length of SQRT(32), what is the length of the hypotenuse?

If you have a 30-60-90 triangle:

13. And the length of the longest leg is 5[SQRT(3)], what's the length of the other leg?
14. Working from #13, what's the length of the hypotenuse?
15. And the length of the longest leg is 9, what is the length of shortest leg?
16. Working from #15, what is the length of the hypotenuse?
17. With a hypotenuse of 2[SQRT(3)] what is the length of the longest leg?
18. Working from #17, what is the length of the shortest leg?
19. And the length of the shortest leg is SQRT(12), what is the length of the longest leg?
20. Working from #19, what is the length of the hypotenuse?

Then I need help with Geometric Probability after. Before I post the questions may I please get some practice questions? Thanks again!!!

## #14 Re: Help Me ! » Pythagorean Theorem - Geometry » 2015-08-09 06:27:46

Thank you for the help.

19. a=6 and c=6(SQRT 2)
6^2 + b^2 = 6(SQRT 2)
36 + b^2 = 72
b^2 = 36
b = 6

I have more lessons to go!

## #15 Re: Help Me ! » Pythagorean Theorem - Geometry » 2015-08-09 06:15:44

Here is what I got:

13. a=7 and c=SQRT 85
7^2 + b^2 = 85
49 + b^2 = 85
b^2 = 36
b = 6

15. a=1 and c=SQRT 2
1^2 + b^2 = SQRT 2
1 + b^2 = SQRT 2
b^2 = 1
b = 1

19. a=6 and c=6(SQRT 2)
6^2 + b^2 = 6(SQRT 2)
36 + b^2 = 24
b^2 = 12
b^2 = SQRT 12

## #16 Re: Help Me ! » Pythagorean Theorem - Geometry » 2015-08-09 03:08:28

Okay here is what I did but I'm still having trouble with 13, 15, and 19.

11.  a=6 and c=12
6^2 + b^2 = 12^2
36 + b^2 = 144
b^2 = 108
b^2 = SQRT 108

12. a=18 and c=30
18^2 + b^2 = 30^2
324 + b^2 = 900
b^2 = 576
b = 24

13. a=7 and c=SQRT 85
7^2 + b^2 =

14. a=1 and c=5
1^2 + b^2 = 5^2
1 + b^2 = 25
b^2 = 24
b^2 = SQRT 24

15. a=1 and c=SQRT 2

16. a=10 and c=12
10^2 + b^2 = 12^2
100 + b^2 = 144
b^2 = 44
b^2 = SQRT 44

17. a=21 and c=35
21^2 + b^2 = 35^2
441 + b^2 = 1,225
b^2 = 784
b = 28

18. a=5 and c=18
5^2 + b^2 = 18^2
25 + b^2 = 324
b^2 = 299
b^2 = SQRT 299

19. a=6 and c=6(SQRT 2)

20. a=11 and c=12
11^2 + b^2 = 12^2
121 + b^2 = 144
b^2 = 23
b^2 = SQRT 23

## #17 Help Me ! » Pythagorean Theorem - Geometry » 2015-08-09 01:06:11

lisathedork
Replies: 8

I was having trouble for the last 10 questions of this lesson.
So far, this is what I got.

What is the value of b if...

11.  a=6 and c=12
6^2 + b^2 = 12
6 + b^2 = 12
b^2 = 12 - 6
SQRT b^2 = SQRT 6
b = 6

12. a=18 and c=30
18^2+ b^2 = 30
18 + b^2 = 30
b^2 = 30 - 18
b^2 = 12
SQRT b^2 = SQRT 3.46
b = 3.46

13. a=7 and c=SQRT 85

14. a=1 and c=5

15. a=1 and c=SQRT 2

16. a=10 and c=12

17. a=21 and c=35

18. a=5 and c=18

19. a=6 and c=6(SQRT 2)

20. a=11 and c=12

I'm pretty sure I'm wrong, but if so can you please explain? The example they are showing me in the lesson is very confusing.

[Example 2:

What is the value of b, if c=SQRT 2 and a=1?

First, we plug the numbers into our theorem:

a2 + b2 = c2

12 + b2 = SQRT 22

Then we simplify:

1 + b2 = 2

Then we solve for b:

b2 = 2 - 1

b2 = 1

Take the square root of both sides:

SQRT b2 = SQRT 1

b = 1]

## #18 Re: Help Me ! » Triangles » 2015-08-09 00:50:06

Yes I did, it pretty much help me with the questions.

## #19 Re: Help Me ! » Triangles » 2015-08-08 08:02:40

Here are my new answers.

13. E

14. A

## #20 Re: Help Me ! » Triangles » 2015-08-08 03:35:37

Thank you for the feedback and yes the questions came from CompuHigh.

## #21 Help Me ! » Triangles » 2015-08-07 11:58:40

lisathedork
Replies: 7

Hello, I was just wondering about these two questions and making sure they were correct. If not, please explain.

13. I have a triangle with sides of 3, 4, and 5, and angles of 30o and 60o. Which of the following would be congruent to it? (You will need to use what you've learned about triangles and angle / side relations, as well as your knowledge of the rules of congruence to fill in the gaps and answer the question. Sketches may be helpful.) Give the reasoning or show your work to support your choice:

A. a triangle with angles of 30o, 60o, and 90o
B. an angle of 90o
C.a triangle with sides of 6, 8, and 10
D. a triangle with sides of 3 and 4
E. a triangle with a side measuring 4, next an angle of 90o, and next a side measuring 3
F. a triangle with a  side measuring 3, next an angle of 60o, and next a side measuring 4

The answer I got for this problem is A.
.

14. I have a triangle with sides of 1 and a side of SQRT(2), with an angle of 45o and an angle of 90o. Which of the following would be congruent to it? (You will need to use what you've learned about triangles and angle / side relations, as well as your knowledge of the rules of congruence to fill in the gaps and answer the question. Sketches may be helpful.). Give the reasoning or show your work to support your choice

A. a triangle with a side of 1, then an angle of 90o, and a side of 1
B. a triangle with a side of 1, then an angle of 90o, then a side of SQRT(2)
C.a triangle with the angles 45o, 45o, 90o
D. a triangle with sides of 1 and 1
E. a triangle with a side of 1, then an angle of 45o, then a side of 1
F. a triangle with an angle of 90o, then a side of SQRT(2), then an angle of 45o

The answer I got for this problem is C.

## #22 Help Me ! » Solving Systems of Equations Using Substitution Method and Elimination » 2013-10-24 09:17:03

lisathedork
Replies: 2

My progress so far, am I'm doing this right?

10.   y = (2/3)x - 1
y = -x + 4

2/3x  1 = -x + 4
2/3x + x = 4 + 1
5/3x = 5

5x = 15
X=3
Y=-x + 4
Y = -3 + 4
Y=1

11.   x + y = 0
3x + y = -4

X + y  (3x + y) = 0  (-4)
X + y  3x  y = 0 + 4
-2x = 4
X= -2

X+ y = 0
-2 + y = 0
Y = 2

12.  4x + 3y = -15
y = x + 2

4x +3(x +2) = -15
4x + 3x + 6 = -15
7x = -21
X = -3

---------------------------------------------------------------------------------------------------------------------------------------------------
Can someone help me guide me through this?

13.   x + 2y = -4
4y = 3x + 12

14.   y = 2x
x + y = 3

15.  x = 3 - 3y
x + 3y = -6

16.   y = -2x + 1
y = x - 5

17.   y = (1/2)x - 3
y = (3/2)x  1

18.   x + y = 2
4y = -4x + 8

19. Why are the substitution and elimination methods necessary when we already know how to solve systems of linear equations using the graphing method?

## #23 Re: Help Me ! » Graphing Systems of Linear Equations » 2013-10-24 09:12:30

I totally understand now. Thanx.

## #24 Re: Help Me ! » Graphing Systems of Linear Equations » 2013-10-24 07:57:54

Shouldn't it be like that?

2x - 3y = -2
2(0) - 3y = -2
-3y = -2
y = 2/3
(0, 2/3)
2x - 3(0) = -2
2x = -2
x = -1
(-1, 0)

4x + y = 8
4(0) + y = 8
y = 8
(0, 8)
4x + y = 8
4x + 0 = 8
4x = 8
x = 2
(2, 0)

these are just examples.

Cause I know I have to found the y = mx + b

## #25 Help Me ! » Graphing Systems of Linear Equations » 2013-10-24 04:31:59

lisathedork
Replies: 5

How do I graph these?

1. y = (2/3)x - 1
y = -x + 4

2. x + y = 0
3x + y = -4

3. 4x + 3y = -15
y = x + 2

4. x + 2y = -4
4y = 3x + 12

5. y = 2x
x + y = 3

6. x = 3 - 3y
x + 3y = -6

7. y = -2x + 1
y = x - 5

8. y = (1/2)x - 3
y = (3/2)x - 1