Question

What are the solutions to the quadratic equation x^2-16=0

Answer 1

Good evening.


This is a incomplete quadratic equation, because it does not have the term bx. Therefore, we can solve this faster with the following strategy:

$\mathsf{x^2 - 16 = 0}$

Add 16 to both sides:

$\mathsf{x^2 - 16 + 16 = 0 + 16}\\ \\ \mathsf{x^2 = 16}$

Take the square root:

$\mathsf{\sqrt {x^2} = \pm\sqrt{16}}\\ \\ \mathsf{\boxed{\mathsf{x = \pm4} }}$

Therefore:

$\boxed{\boxed{\mathsf{S=\{-4, \ +4\}}}}$