Answer:
x² + 7x + 49/4 = (x + 7/2)²
Step-by-step explanation:
x² + bx + c is a perfect square when c = (b/2)².
b = 7, c = (7/2)² = 49/4.
x² + 7x + 12.25 = (x+3.5)²
(a+b)² = a²+ 2ab + b²
then:
7x = 2ab
7/2 = 3.5
(x+3.5)² = x² + 2*3.5*a + 3.5²
