Question

Which equation shows the quadratic formula used correctly to solve 7x2 = 9 + x for x?

Answer 1

I hope this helps you

Answer 2

Answer:

Quadratic formula for given equation is $x=\frac{-(-1)\pm\sqrt{(-1)-4(7)(-9)}}{2\times7}$

Step-by-step explanation:

Given Quadratic Equation is  7x² = 9 + x

We need to find correct Quadratic formula for the given quadratic equation.

If the quadratic equation is in standard for,

ax² + bx + c = 0

then quadratic formula is given by,

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

First we rewrite the quadratic equation,

7x² - x - 9 = 0

by comparing with standard form of equation we get,

a = 7  ,   b = -1  and c = -9

oNw putting these value in quadratic formula we get,

$x=\frac{-(-1)\pm\sqrt{(-1)-4(7)(-9)}}{2\times7}$

Therefore, Quadratic formula for given equation is $x=\frac{-(-1)\pm\sqrt{(-1)-4(7)(-9)}}{2\times7}$