What is the height of a rectangle is three more than twice its base, b. The perimeter of this rectangle is 60 cm.

Answer 1

h=3+2b

2h+2b =60

2(3+2b) + 2b = 60

6 +4b + 2b =60

6b = 54

b = 9

h=3+2(9) = 21 cm

Answer 2

the height h = 3+2b, and the perimeter is L= 2h + 2b = 6+4b+2b = 60,

so b = 9, and h = 21 .