For substitution it would be -4/3 (2) +6 and then you solve!
The solutions are where the lines intersect
solution to p(x) and f(x) is (6,2)...because this is where they intersect
solutions to f(x) are : (6,2) and (3,6)
solution to p(x) and g(x) is (3,6)
P = 2(L + W)
P = 25
L = W + 3
now we sub and solve
25 = 2(W + 3 + W)
25 = 2(2W + 3)
25 = 4W + 6
25 - 6 = 4W
19 = 4W
19/4 = W
4.75 = W <== width = 4.75 cm (or 4 3/4 cm)
L = W + 3
L = 4.75 + 3
L = 7.75 <== length = 7.75 cm (or 7 3/4 cm)