See attachment for reply and answer.
Answer:
i guess it's will be C
Step-by-step explanation:
x^2 = 2x + 15
x^2 -2x - 15 = 0
Factor:
(x-5)(x+3) = 0
x = 5 or x = -3
(4×4)_7
16_7
=9 as the answer
