what value of c makes x^2 - 24x + c a perfect square trinomial?

Answer:
Step-by-step explanation:
Quadratic equation is given by x²-24x+c
This is in the form expansion of (a-b)², that is a²-2ab+b²
Comparing
a² = x², a = x
-2ab = -24x
-2xb = -24x
b = 12
c = b² = 12² =144
x²-24x+144 = (x-12)²
Option D is the correct answer