In △XYZ, XY=XZ. Find the perimeter of △XYZ if XY=2a, YZ=3a+1, and XZ=5a-12.

Perimeter = 10a - 11

Step-by-step explanation:

In triangle XYZ, the 3 sides are XY, YZ, and XZ.

The perimeter of a triangle is sum of the 3 sides.

For this problem, the perimeter = XY + YZ + XZ

Putting in the information given, we get:

Perimeter = 2a + (3a+1) + (5a-12)

Adding like terms, we get:

= 2a + 3a + 1 + 5a - 12

= 10a - 11