Can you guys please help me with this? I will give brainliest and 20 points if you help me.

Step-by-step explanation:

1) a) equations: 3x+21 and 6x -60

b) value of x: 3x+ 21=6x-60  ( set them equal to each other because they are equal, then solve)

3x+21=6x-60

-3x=-81

x= 27

c) replace 27 in both equations to find the angle measure.

3(27)+21= 102

6(27)-60= 102

2) a) equations: 12x-18 and 8x+10

b) value of x:   12x-18=8x+10( set them equal to each other because they are equal, then solve)

12x-18=8x+10

4x=28

x= 7

c) replace 7 in both equations to find angle measure.

12(7) -18 = 66

8(7)+10= 66

angle measure: 66

3) a) equations: 7x+9 and 5x+3

b) value of x: to find value of x here, first know that the these two equations will add up to 180. So, set them up to be equal to 180.

7x+9+5x+3=180

Then solve.

12x+ 12=180

12x=168

x=14

c) angle measure: replace the 14 in the x of the two equations.

7(14) +9 = 107

5(14) +3= 73

add the two angle measure together to see if they add up to 180.

107 + 73 = 180 correct! :D

can someone answer this question plz

step-by-step explanation:

proofs involving isosceles triangles often require special consideration because an isosceles triangle has several distinct properties that do not apply to normal triangles.(more about triangle types) therefore, when you are trying to prove that two triangles are congruent, and one or both triangles, are isosceles you have a few theorems that you can use to make your life easier.

step-by-step explanation:

an isosceles triangle has two congruent sides and two congruent angles. the congruent angles are called the base angles and the other angle is known as the vertex angle. ∠bac and ∠bca are the base angles of the triangle picture on the left. the vertex angle is ∠abc