Question

How to solve an equation using factoring and quadratic formula ? x^+15x-54=0?

Answer 1

X^2+18x-3x-54=0
x(x+18)-3(x+18)=0
x=3, -18

Answer 2

For factorizing,
Find two numbers whose product is -54 and sum is 15
18 & -3
\[x^2+18x-3x-54=0\]
\[x(x+18)-3(x+18)=0\]
\[(x+18)(x-3)=0\]
x={-18,3}

Answer 3

thanks

Answer 4

For quadratic formula,
ax^2+bx+c=0

\[x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}\]

So it would be
\[\frac{-15 \pm \sqrt{225+ 216}}{2}\]
=6,-18

Answer 5

okay thank you

Answer 6

same equation, different roots..how come?
its 3 and -18

Answer 7

Uh sorry, typo, its 3,-18