Question

Use the X intercept method to find all real solutions of the equation x^3-10x^2+17x+28=0

Answer 1

Answer:

A. -1, 4, 7

Step-by-step explanation:

Answer 2

Answer:

They are -1, 4 and 7.

Step-by-step explanation:

x^3 - 10x^2 + 17x + 28 = 0

Observation of this equation shows that there is an x -intercept at x = -1 because

-1^3 - 10^(-1)^2 - 17(1) + 28 =   -28 + 28

= 0.

So x + 1 must be a factor so we can do the division:

x + 1 ) x^3 - 10x^2 + 17x + 28 ( x^2 - 11x + 28

          x^3 + x^2

                 -11x^2 + 17x

                 -11x^2 - 11x

                               28x^2 + 28

x^2 - 11x + 28 = ( x - 4)(x - 7)

x = 4, 7.