Question

Simplify the following expression and evaluate them as directed:
$3y(2y-7)-3(y-4)-63$ for $y=-2$

Answer 1

$3y(2y-7)-3(y-4)-63$

= $3y.2y-3y.7-3.y+3\times 4-63$

$=6y^2-21y-3y+12-63$

$=6y^2-24y-51.$

for $y=-2$ in expression

$6y^2-24y-51=6(-2{)}^2-24(-2)-51$

$=6\left(4\right)+48-51$

$=24+48-51$

= $72-51$

= $21.$