the complete question in the attached figure
we know that
perimeter of a rectangle=2*[base+height]
rectangle P
perimeter=20 in
perimeter=2*[j+4+h]
20=2j+2h+8------> 2j+2h=12----> j+h=6-----> j=6-h------> equation 1
rectangle Q
perimeter=30 in
perimeter=2*[j+1+3h]
30=2j+6h+2----> 2j+6h=28----> j+3h=14-------> equation 2
substitute equation 1 in equation 2
(6-h)+3h=14-----> 2h=8-----> h=4
j=6-h-----> j=6-4----> j=2
the answer is
j=2
h=4
