Question

What is the factored form of 4x2 + 23x – 72?

Answer 1

4x2 + 23x – 72 
= (4x - 9)(x+8)

hope that helps

Answer 2

Answer:

$4x^{2} +23x-72=(4x-9)(x+8)$

Step-by-step explanation:

we have

$4x^{2} +23x-72$

Equate the quadratic equation to zero

$4x^{2} +23x-72=0$

Group terms that contain the same variable, and move the constant to the opposite side of the equation

$4x^{2} +23x=72$

Factor the leading coefficient

$4(x^{2} +(23x/4))=72$

Complete the square. Remember to balance the equation by adding the same constants to each side

$4(x^{2} +(23x/4)+(529/64))=72+(529/16)$

$4(x^{2} +(23x/4)+(529/64))=1681/16$

$(x^{2} +(23x/4)+(529/64))=1681/64$

Rewrite as perfect squares

$(x+(23/8))^{2}=1681/64$

square root both sides

$(x+(23/8))=(+/-)41/8$

$x=-(23/8)(+/-)41/8$

$x=-(23/8)+41/8=18/8=9/4$

$x=-(23/8)-41/8=-64/8=-8$

therefore

$4x^{2} +23x-72=4(x-9/4)(x+8)$

$4x^{2} +23x-72=(4x-9)(x+8)$