Answer:
Step-by-step explanation:
y+30+2y=180
Add like terms
3y+30=180
Subtract 30 on both sides
3y=150
Divide by 3 on both sides
y=50
Now all you have to do i calculate the angles.
10
Area of traingle:1/2
50=1/2.10.x
50=5x
50/5=5x/5
x=50/5
x=10
c i think because the problem =-
11. D Square pyramid
12. A Cube
