Answer:
Part A & B
Step-by-step explanatPart A:
f(x) = 4x ^ 2 - 7x - 15
0 = 4x ^ 2 - 7x - 15
a = 4, b = -7, c = -15
a x c = -60
-12 x 5 = -60
-12 + 5 = -7
(4x + 5)(4x - 12)
4x ^ 2 - 12x I + 5x - 15
4x(x - 3) + 5(x - 3)
(x - 3)(4x + 5)
x = 3 x = -1.25 or -5/4
Part B:
Minimum point
(x1 + x2)/2
(3 -1.25)/2 = 0.875
f(x) = 4x ^ 2 - 7x - 15
f(0.875) = 4(0.875) ^ 2 - 7(0.875) - 15
f(0.875) = 3.06 - 6.125 - 15
f(0.875) = -18.065ion: