For what value of x

Question

is the square of the binomial x+1 twenty greater than the square of the binomial x–3?

is the square of the binomial x+1 twenty greater than the square of the binomialx–3?

Answer 1

Set the equation

 

(x + 1)² - (x - 3)² = 20

 

 

Expand the terms.

 

x² + 2x + 1 - (x² - 6x + 9) = 20

 

8x - 8 = 20

 

 

Add 8 on both sides of the equation.

 

8x = 28

 

 

Divide both sides of the equation by 8.

 

x = 3.5

 

 

This means that the square of (x + 1)² is 20 greater than (x - 3) when the value of x is 3.5

Answer 2

(X+ 1)² = (x - 3)² + 20

 

x² + 2x + 1 = x² - 6x + 9 + 20

     

        2x + 1 = - 6x + 29

 

              8x = 28

 

                x = 3.5

 

when x = 3.5 the statement is true