Fifteen times the square of an non- zero number is equal to 20 times the number

"Fifteen times" = 15 times a number
"square of an non-zero number" = x times itself (x^2)

"Fifteen times the square of an non- zero number" = 15 times x^2 = 15x^2

"20 times" = 20 times a number
"the number" = same number as the first term: x

"20 times the number" = 20x

The equation can be written as follows:



Divide both sides by x:



Divide both sides by 15 to get x by itself: