How do you simplify -5d + 3 (2d - 7)?

Apr 13, 2016

$= d - 21$

Explanation:

$- 5 d + 3 \left(2 d - 7\right)$

$= - 5 d + 3 \cdot \left(2 d\right) + 3 \cdot \left(- 7\right)$

$= \textcolor{b l u e}{- 5 d + 6 d} - 21$

$= d - 21$