Question

Find the sum of all solutions to the equation $3x(x+4) = 66$

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

-4

Step-by-step explanation:

The given equation is

$3x(x+4)=66$

On simplification we get

$3x^2+12x=66$

Divide both sides by 3.

$x^2+4x=22$

$x^2+4x-22=0$

If a quadratic equation is defined as $ax^2+bx+c=0$, then the sum of solutions is -b/a.

In the above equation a=1, b=4 and c=-22.

Sum of solutions $=-\dfrac{b}{a}=-\dfrac{4}{1}=-4$

Therefore, the sum of all solutions is -4.