The perimeter of a floor is 40m. The length is
three times as long as the widtb.
(a) What is the length of this floor?
(b) What is its area ?

Step-by-step explanation:

(a) Let L represent the length of the floor. The length is 3 times the width, so we have L = 3W, or W = L/3.

  P = 2(L+W) . . . . the formula for the perimeter of a rectangle

Filling in the known values, we have ...

  40 = 2(L +L/3)

  20 = (4/3)L . . . . divide by 2 and collect terms

  15 = L . . . . . . . . multiply by 3/4

The length of the floor is 15 m.

__

(b) From above, the width is ...

  W = L/3 = (15 m)/3 = 5 m.

The area is given by the formula ...

  A = LW = (15 m)(5 m)

  A = 75 m²

The area of the floor is 75 square meters.

answer: 0

step-by-step explanation: the positive, like 5, + its opposite, like -5 would be 0

5+(-5)=0, or 5-5=0