Hi there!!
Your answer is 20.
Since A = 40 and B = 20
Subtract 40 by 20 to get 20 (40 - 20 = 20)
Hope I Helped
60x - 12 = 14x^2 + 14x
Subtract 60x & Combine
-12 = 14x^2+14x-60x
-12= 14x^2-46x
Add 12
0= 14x^2-46x-14
The answer is 315 as the formula is : a+b/2•h.