Question 921613
The diagonals of a parallelogram bisect each other.
They intersect at S, so S is
the midpoint of diagonal BT (which we do not care about),
and the midpoint if diagonal AH (which means HS=AS, and AH=2HS).
{{{system(HS=10x+7,AS=5x+22,HS=AS)}}}--->{{{10x+7=5x+22}}}--->{{{10x+7-5x-7=5x+22-5x-7}}}--->{{{10x-5x=22-7}}}--->{{{5x=15}}}--->{{{x=15/5}}}--->{{{x=3}}}
So, {{{HS=10x+7}}} means {{{HS=10*3+7}}}--->{{{HS=30+7}}}--->{{{HS=37}}} ,
and HA=2HS means {{{HA=2*37}}}--->{{{highlight(HA=74)}}} .