-7(1+5m)-29<300+7m expand Left side
-7 - 35m - 29 < 300 + 7m simplify by gathering 'like' terms
-42m < 336 divide by - 42 ( this reverses the < to > )
m > 336/(-42)
m > -8
\(-7\left(1+5m\right)-29<300+7m\)
\(-35m-36<300+7m\)
\(-35m-36+36<300+7m+36\)
\(-35m<7m+336\)
\(-35m-7m<7m+336-7m\)
\(-42m<336\)
\(\left(-42m\right)\left(-1\right)>336\left(-1\right)\)
\(42m>-336\)
\(\frac{42m}{42}>\frac{-336}{42}\)
\(m>-8\)
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