4x+1.5y=12.20
5x+2y=15.40
find x and y using simeltaneous equations
y=-3x^{2}+6x+9
5/3-1
(1)*($x^{2}$-1)*($x^{2}$+2x-15)
3 $\sqrt{20}$ +2 $\sqrt{\45}$ + $\sqrt{80}$
2-\left(\ \frac{\ 1}{2}-\left(\ \frac{\ 3}{4}\right)\cdot \ \frac{\ 8}{2}+1\right)-\left(\ \frac{\ 4}{3}\right)^2
-14 x 8/5
\frac{4x-7}{3}-\frac{2x-5}{5}=\frac{1}{4}
x(x+7)(x-2)
make H the subject of this formula: q=ch+s
