Question

solve and graph: 5x^2+9x<2

Answer 1

@texaschic101

Answer 2

bring \(2\) on the LHS and factor the quadratic ,


\(\large \color{black}{\begin{align} 5x^2+9x&<2\implies \hspace{.33em}\\~\\
5x^2+9x-2&<0\hspace{.33em}\\~\\

\end{align}}\)

Answer 3

@xokatexo do you understand the part @mathmath333 explained?

Answer 4

yeah but my answers were 1/5 and -2 are those right?

Answer 5

Well now you have to know how to factor it!

Answer 6

well i dont can you help

Answer 7

for factoring quadratic note that

\(\large \color{black}{\begin{align}
\color{red}{5}x^2+9x-\color{red}{2}&<0\hspace{.33em}\\~\\
\end{align}}\)

\(5\times 2=10\)

and \(9x\) can be written as \(10x-x\)


\(\large \color{black}{\begin{align}
\color{red}{5}x^2+ \color{blue}{10}x- \color{blue}{1}x-\color{red}{2}&<0\hspace{.33em}\\~\\
\end{align}}\)

Answer 8

You can do this either by some methods or by using calculators

Answer 9

are 1/5 and -2 right?

Answer 10

Yes your answer is right!

Answer 11

I factored it and it was right!

Answer 12

so u can write this as

\(\large \color{black}{\begin{align}
-2<x<\dfrac {5}{2}\hspace{.33em}\\~\\
\end{align}}\)

Answer 13

and then idk what points to test

Answer 14

u have to just represent that in number line.

Answer 15

so think about it and try

Answer 16

i know -3 and 0 but idk what for the third one

Answer 17

u have solve the equation the solution is
\(\large \color{black}{\begin{align}
-2<x<\dfrac{5}{2}\hspace{.33em}\\~\\
\end{align}}\)

now u hav
e to just graph it.

x is between the point \(-2\) and \(\dfrac 52=2.5\)

Answer 18

note that i have used \(\huge ^{\circ}\) between the lines due to the sign \(<\)

Answer 19

i got 1/5 not 5/2

Answer 20

o, ok sry my mistake

Answer 21

use the fact that \(\dfrac{1}{5}=\dfrac{2}{10}=0.2\)