Answer:
16cm by 5cm
Explanation:
P=2(l+w)
A= wl
80 factorization: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80.
you then would have to find 2 numbers that would add up to make 42.
When you try 16*2+5*2= 32+10= 42 cm as your perimeter.
16*5= 80 cm^2 as your area.