## Algebra 1

$y=-3$
Distribute 5 and 7 to have: $5y-20=14y+7$ Subtract $7$ from both sides to have: $5y-20-7=14y+7-7 \\5y-27=14y$ Subtract $5y$ from both sides to have: $5y-27-5y=14y-5y \\-27=9y \\-3 = y$ Checking: $\begin{array}{ccc} \\5(-3-4) &\stackrel{?}{=}&7[2\cdot(-3)+1] \\5(-7) &\stackrel{?}{=}&7[-6+1] \\-35 &\stackrel{?}{=}&7(-5) \\-35 &\stackrel{\checkmark}{=}&-35 \\\end{array}$