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yup totally agree ...... no I still need to take 1 more math course

for #8

I know how annoying I said it was D because B was incorrect if thats incorrect to then I give up

yup A was correct but I got 2 incorrect #6, #8

6. Calculate the area of the regular octagon shown.

6.B

I choose B because area = (½)(apothem)(perimeter)

1/2 * 3.8 * 48 = 91.2

8.I still think it is B I cant really find what I did incorrect for this one I really need a clue.

I used the Pythagoras to get the missing side I got 2.38 Then I used cosine= A/H 9/11 = 0.82

cos-¹ = 34.92 So that is angle A

90+34.92=124.92

So angle B = 180 - 124.92 = 55.08

A= 34.92

B= 55.08

C= 90

So its really asking for that triangle area

2*PI*6*16=192PI

or 603.19

So A can be the answer

I still get B

2×(36×pi)+603.2 = 829.39

36pi is the circle area

then the area of the triangle is= 12pi( circumference of the circle ) * (16) = 192PI or 603.2

SA = 2×(36×pi)+603.2 = 829.39

I choose B and it was incorrect still cant find the answer

16. A right circular cylinder has a base diameter of 12 meters and a height of 16 meters. What is the approximate total lateral surface area of the cylinder?

A 602.9 m²

B 829.4 m²

C 1507.2 m²

D 2034.7 m²

So what I did isn't incorrect right? but I answered B and it was incorrect

8. Select which statement is true about the relationship between the measures of angle A and angle B in the diagram shown.

A The measure of angle A is greater than the measure of angle B .

B The measure of angle B is greater than the measure of angle A.

C The measure of angle A is equal to the measure of angle B .

D Cannot be determined without any other calculations.

#8- Ok so I first choose B but I still see that my answer is correct

because the measure of the missing angle would 2.38

Then I use cosine= A/H

9/11 = 0.82

cos-¹ = 34.92

So that is angle A

90+34.92=124.92

So angle B = 180 - 124.92 = 55.08

A= 34.92

B= 55.08

C= 90

I thought you meant reverse the statements

So B is the answer

So A would be correct?

I need help solving this I choose D and it was incorrect

11. Which is the contrapositive of the following statement? If quadrilateral ABCD is a rectangle, then quadrilateral ABCD is a square.

A If quadrilateral ABCD is a square, then quadrilateral ABCD is a rectangle.

B If quadrilateral ABCD is not a square, then quadrilateral ABCD is not a rectangle.

C If quadrilateral ABCD is not a rectangle, then quadrilateral ABCD is not a square.

D If quadrilateral ABCD is not a square, then quadrilateral ABCD is a rectangle.

Ok first I choose B

My correction is :

area = (½)(apothem)(perimeter)

1/2 * 3.8 * 48 = 91.2

6. Calculate the area of the regular octagon shown.

A 21.9 square meters

B48.0 square meters

C91.2 square meters

D350.4 square meters

I choose A and it was incorrect still confused

Ok so Obtuse Triangle has an angle that is more than 90° So that means only one angle is more than 90° and an isosceles triangle has two equal sides and two equal angles. So am thinking the last picture

5. Which triangle is an obtuse isosceles triangle?

Yeah I sure did I drew it on my note book then found out how easy the question was I sure will try it next time

I corrected the following :

I choose D and it was incorrect

now I choose C

because adjacent angles are supplementary

AD = EH

FG=BC

So A= x

b = 180 - x

So D is X F= 180-x

So the angles are supplementary because they add up to 180

4. Which statement about angle 1 and 2 must be true?

A angle 1 is congruent to angle 2

B- 1 is the complement of angle 2

C- angle 1 is the supplement of angle 2

D- Angle 1 and 2 are vertical angles

If I say the distance from B to c is 2

then AB would be 10-2=8

DE = 5 and I know that DE is half of CE So CE would equal CD*2 So CE=10

DE=5

CD=5

CE= 10

AC= 10

So AE= 20

I choose D because I didn't read the question correctly ammm but can I use the distance formula to get the answer ?

3. In the figure shown, line segment AC = CE , D is the midpoint of CE , DE=5, and BC=2 . What is the measure of AB ?

A 5

B7

C8

D10

yeah its a typo

yup I mean x

So x is the large than the small angle is x-35

So x+x-35=90

x+x= 2x

-35+2x=90

-(-35) -(-35)

2x=125

x = 62.5

So the measure of the larger angle is 62.5

So the equation would be x + y - 35 = 90 right?

I choose B because Complementary angles are two angles whose measures total 90 degrees.

90 - 35 = 55 and it was incorrect.

1. Two angles are complementary. The smaller angle is 35° less than the larger angle. What is the measure of the larger angle?

A- 27.5°

B- 55°

C- 62.2°

D- 125°

I submitted my work I got 12/20 So 8 wrong

Thank you