Remember that
If two triangles are similar, then the artio of its corresponding sides is proportional
so
Part 1
triangle PQR and PFG are similar
that means
PQ/PF=PR/PG
substitute the given values
27/(2x-9)=27/(9)
so
2x-9=9
2x=18
x=9
Part 2
we have
triangle ABC is similar to triangle AVW
that means
AB/AV=AC/AW
substitute the given values
182/(10x+5)=196/(70)
solve for x
182*70=(10x+5)*196
12,740=1,960x+980
1,960x=12,740-980
1,960x=11,760
x=6