How to solve this problem using the quadratic formula?

Question

x^2 -3x-7=0

Basically I don't know if I should add or subtract the square root of b squared.
Please Help!

Answer 1

x = [ 3 ± √(9 + 28) ] / 2
x = [ 3 ± √(37) ] / 2
x = 4.54 , x = - 1.54

Answer 2

You do both to get two solutions.

So in your case, you get:

(3 +/- sqrt(37)) / 2

So one solution is x=(3+sqrt37)/2 and the other is (3-sqrt37)/2