Question

A triangle has a perimeter of 40cm. If the three sides of the triangle are n, 3n−5, and 3n−4, what is the length of each side?

Answer 1

9514 1404 393

Answer:

7, 16, 17

Explanation:

The sum of the lengths of the three sides is the perimeter:

(n) +(3n -5) +(3n -4) = 40

7n -9 = 40 . . . . . . . . . . . . . . collect terms

7n = 49 . . . . . . . . . . . add 9

n = 7 . . . . . . . . . divide by 7

Then the side lengths are ...

n = 7

3n -5 = 16

3n -4 = 17