P / 9 = 72
Multiply both sidess by 9
P / 9 (9) = 72 (9)
p = 648
2 because u divide 8 by 4 and u get the answer 2
By the way the arrow is pointing?
Wa=0.5Wb, Ha=20, Hb is unkown
the area of rectangle a is : Wa*20
the area of rectangle b is : Wb*Hb
Rectangle a has 7 times the area of rectangle b: Wa*20=7*Wb*Hb
Replace Wa with 0.5Wb: 0.5Wb*20=7Wb*Hb => Hb=10/7
