Question

Solve the inequality: x^2-3x-18<0

Answer 1

factor the left side of the inequality

Answer 2

oh and?...

Answer 3

x^2 - 3x - 18 < 0
x^2 - 3x < 18
x^2 - x > - 6 * you would switch the inequality sign because you divided by a negative.
x > 12
I'm pretty sure that would be the answer, I'm not 100% though.

Answer 4

here's the detail
\[x^{2}-3x-18<0\]
\[\left( x+3 \right)\left( x-6 \right)<0\]

Answer 5

\[x^2 - 3x -18 < 0\]
\[(x-6)(x+3)\]
This would lead to:
\[x-6 < 0\] or \[x+3<0\]

Which means that either
\[x<6\] or\[x<-3\]

Treat the inequality as if it were an equation but be mindful that by multiplying or dividing by minus signs changes the direction of the inequality sign

Answer 6

the roots of the left hand side are -3 and 6
choose a value in each intervals \[x<-3\] \[-3<x<6\] \[6<x\]

Answer 7

comment on Muli97 solution
if \[\left( x+3 \right)\left( x-6 \right)<0\]
then one factor is positive and the other factor is negative