Question

Factor the expression on the left side of the equation. Then solve the equation.

x³ - 2x² - 5x = 0

-5, 0, 3
0, -1 ± √24
0, -1 ± √6
0, 1 ± √6

Answer 1

x³ - 2x² - 5x = 0

First, take common factor:

x(x^2 - 2x - 5 )= 0

Now use the quadratic formula to find the roots of the trinomial

x = [- b +/- √(b^2 - 4(a)(c)] / 2a


`x = (2 +/- √(4 -4(1)(-5)) )/(2)`

x = [2 +/-2√6 ]/2

x = 1 + √6 and x = 1 -√6

Then the solutions are:

x =0; x = 1 + √6; x = 1 - √6

That is the las option shown.