what is the length of each side?

Question

A triangle has a perimeter of 71cm. If the three sides of the triangle are n, 4n+3, and 4n−4, what is the length of each side?

Separate multiple entries with a comma.

Answer 1

The perimeter of a triangle is the sum of the lengths of the sides,

Thus,

n + (4n + 3) + (4n - 4) = 71
n + 4n + 4n + 3 - 4 = 71
9n - 1 = 71
9n = 71 + 1
9n = 72
9n/9 = 72/9
n = 8

The sides are:
  n = 8
  4n + 3 = 4(8)+3 = 32+3 = 35
  4n -  4 = 4(8)-4 = 32-4 = 28

Perimeter:
  8 + 35 + 28 = 71