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#26 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

#27 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]

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

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

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

Here are my new answers.

13. E

14. A

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

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

#31 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.

#32 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?

#34 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

#35 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

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