X=hours master worked
y=hours apprentice worked
62x+40y=492
if master worked 3hours more than apprntice
x=3+y
sub 3+y for x
62(3+y)+40y=492
expand
186+62y+49y=492
186+102y=492
minus 186 both sides
102y=306
divide both sides by 102
y=3
sub back
x=3+y
x=3+3
x=6
master electrician worked 6 hours
6*62=372
master electrician earned $372
A=8ft^2
A=l•w
8=l•w
l=8/w
P=2(l+w)
12=2(8/w+w)
12=2(8/w+w/1)
12=2(8/w+w^2/w)
12=16w^2/w
12=16w
w=12/16
w=3/4=0.75ft
l=8/0.75=10.67ft