Answer:
x = {-4, 4}
Step-by-step explanation:
Subtracting 3 gives ...
5x^2 = 80
Dividing by 5, we get ...
x^2 = 16
Taking the square root gives the solutions ...
x = ±4
The smaller value of x is -4; the larger value is 4.
I am pretty positive that it is b...