Question

Work out the perimeter of this isosceles triangle.
All of the sides are in cm.

Answer 1

38 cm.

Explanation:

Two sides are equal ( as its an isosceles triangle). so:

3x - 5 = 19 - x

3x + x = 19 + 5

4x = 24

x = 6.

So the perimeter

= 3x - 5 + 19 - x + 2x

= 3(6) - 5 + 19 - 6 + 2(6)

= 18 - 5 + 19 - 6 + 12

= 49 - 11

= 38 cm.