Answer:
The answear is C
Step-by-step explanation:
The solution of the equation x2+7x is 0, -7 using the quadratic formula.
x2 + 7x = 0
-b ± √ b2 - 4(ac)/ 2a
substitution,
a = 1, b = 7, c = 0
= -7 ± √(7)2 - 4(1 x 0) / 2 x 1
= - 7 ± 7 / 2
x = 0 , -7
4x(3x+7)
60%
$64*.60= $38.40
