SOLUTION: what is the hieght of rectangle if the perameter is 40 m and the base is four less then five times the height

Algebra ->  Rectangles -> SOLUTION: what is the hieght of rectangle if the perameter is 40 m and the base is four less then five times the height      Log On


   

Question 295119: what is the hieght of rectangle if the perameter is 40 m and the base is four less then five times the height
Answer by blwinbbbles(106) About Me  (Show Source):
You can put this solution on YOUR website!
h=height b=base
Start with what we know: a perimeter of a rectangle is all sides add together so you can say:
b+b+h+h = periameter or 40 m
so: 2b+2h=40
and we know that the base = 5 times the height minus 4 so:
b=5h-4 now we have two equations:
1) 2b+2h=40
2) b= 5h-4 use substitution
2(5h-4)+2h =40
10h-8+2h=40
12h-8=40 add 8 to both sides
12h=48 divide by 12
h=4
now go back to the equations and use 4 for b
1) 2(4)+2h=40
8+2h=40 subtract 8 from both sides
2h=32 divide by 2
h = 16
so the base is 16m and the height is 4m