Question

Find the product:

$\left(i\right)x+y-10and12xy$.

$\left(ii\right)\left(\frac{4}{6}\right)aband\left(\frac{-3}{10}\right)x^{2}y$

$\left(iii\right)(x+y+z+p)andxyzp$

$\left(iv\right)2x^2+6xy-24and3ab$ [4 MARKS]

Answer 1

Application: 1 Mark each

$\left(i\right)(x+y-10)\left(12xy\right)$

$=12x^{2}y+12x{y}^2-120xy$


$\left(ii\right)\left\{\right(\frac{4}{6}\left)ab\right\}\left\{\right(\frac{-3}{10}\left)x^{2}y\right\}$

$=\left(\frac{4}{6}\right)\left(\frac{-3}{10}\right)ab{x}^{2}y$

$=\frac{-12}{60}ab{x}^{2}y$

$=\frac{-1}{5}ab{x}^{2}y$


$\left(iii\right)(x+y+z+p)\left(xyzp\right)$

$=x^{2}yzp+x{y}^{2}zp+xy{z}^{2}p+xyz{p}^2$


$\left(iv\right)(2x^2+6xy-24)\left(3ab\right)$

$=6x^{2}ab+18abxy-72ab$