Question

Determine the correct set up for solving the equation using the quadratic formula 4x^2-5=3x+4

Answer 1

You need to subtract everything to the left side and set it equal to zero. Combine like terms.

Then, the coefficient of x^2 is a, the coefficient of x is b, and the constant term is c.

4x^2 - 5 = 3x + 4

4x^2 - 3x - 5 - 4 = 0

4x^2 - 3x - 9 = 0

a = 4; b = -3; c = -9

$x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}$

$x = \dfrac{-(-3) \pm \sqrt{(-3)^2 - 4(4)(-9)}}{2(4)}$