Question
Simplify the expression and evaluate as directed: $3y(2y – 7) – 3(y – 4) – 63$ for $y = –2$
✓
Answer
$3y(2y – 7) – 3(y – 4) – 63$
$= 6y^2- 21y – 3y + 12 – 63$
$= 6y^2– 24y – 51$
For $y = –2$,
$6y^2– 24y – 51 = 6(–2)^2– 24(–2) – 51$
$= 6 × 4 + 24 × 2 \;– 51$
$= 24 + 48 – 51 = 72 – 51 = 21$
$= 6y^2- 21y – 3y + 12 – 63$
$= 6y^2– 24y – 51$
For $y = –2$,
$6y^2– 24y – 51 = 6(–2)^2– 24(–2) – 51$
$= 6 × 4 + 24 × 2 \;– 51$
$= 24 + 48 – 51 = 72 – 51 = 21$
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