Question

Solve the quadratic equation below for the exact values of x: 4x^2-5=75

Answer 1

Step-by-step explanation:

$4 {x}^{2} - 5 = 75 \\ 4 {x}^{2} = 75 + 5 \\ 4 {x}^{2} = 80 \\ {x}^{2} = \frac{80}{4} \\ {x}^{2} = 20 \\ x = \pm \sqrt{20} \\ x = \pm 2 \sqrt{5}$