Hello!
Simplifying:
5x^2 + -90 = 0
Reorder the terms:
-90 + 5x^2 = 0
Solving:
-90 + 5x^2 = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '90' to each side of the equation.
-90 + 90 + 5x^2 = 0 + 90
Combine like terms: -90 + 90 = 0
0 + 5x^2 = 0 + 90
5x^2 = 0 + 90
Combine like terms: 0 + 90 = 90 5x^2 = 90
Divide each side by '5'.
x^2 = 18
Simplifying:
x^2 = 18
Take the square root of each side:
x = {-4.242640687, 4.242640687}
Hope this Helps! Have A WONDERFUL Day! :)