[tex](4x+3)(x-7)=90\\
Distribute\\
4x^{2}-28x+3x-21=90\\
4x^{2}-25x-21=90\\
4x^{2}-25x-101=0\\
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101\ is\ a\ prime\ number,\ so\ use\ the\ quadratic\ equation.\\
x= \frac{-b+-\sqrt{b^{2}-4ac}}{2a} \\
\frac{-(-25)+-\sqrt{(-25)^{2}-4*4*(-101)}}{2*4} \\
\frac{25+-\sqrt{625+1616}}{8} \\
x= \frac{25+-\sqrt{2241}}{8} \\
So\ x= \frac{25+\sqrt{2241}}{8}\ and x= \frac{25-\sqrt{2241}}{8} \\
These\ come\ out\ to\ be\ x=9.0424... \ and\ x=-2.7924...[/tex]
