Question 1133499
<pre>
SIDE               LENGTH      LENGTH VALUE
first               y-3         4
second               y          7
third              4(y-3)      16
PERIMETER           27

{{{y-3+y+4y-12=27}}}
-
{{{6y-15=27}}}
{{{6y=27+15}}}
{{{6y=42}}}
{{{highlight_green(y=7)}}}
</pre>