Answer:
x = 15
Step-by-step explanation:
Angle Formed by Two Secants
= 1/2(DIFFERENCE of Intercepted Arcs)
2x +15 = 1/2 (10x+20 - 80)
Multiply by 2
4x+30 = (10x+20 - 80)
Combine like terms
4x+30 = 10x-60
Subtract 4x from each side
30 = 6x-60
Add 60 to each side
90 =6x
Divide by 6
15 =x
