a teacher writes the following product on the board (3x) (x^2+6) = 3x^3 + 18x Eduardo says that 3x^3 + 18x is a factor of 3x

3a teacher writes the following product on the board (3x) (x^2+6) = 3x^3 + 18x Eduardo says that 3x^3 + 18x is a factor of 3x

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: