Question

What are the solutions to the quadratic equation 4x2 = 64?

x = −16 and x = 16
x = −8 and x = 8
x = −4 and x = 4
x = −2 and x = 2

Answer 1

the 3rd one x = -4 and x = 4.

Answer 2

Answer:

Option 3rd is correct

x = -4 and x = 4

Step-by-step explanation:

Given the equation:

$4x^2 = 64$

Divide both sides by 4 we have;

$x^2 = 16$

Take square root both sides we have;

$\sqrt{x^2} = \pm \sqrt{16}$

Simplify:

$x = \pm 4$

Therefore, the solution for the given equation are:

x = -4 and x = 4