Start with evaluating the side length by dividing the perimeter by 3.
QR=2a+3b
We are given that equilateral triangle MNP has perimeter 12a+18b. Since an equilateral triangle has three congruent sides, we can evaluate the side length by dividing its perimeter by 3.
The side length of â–³ MNP is 4a+6b. Now, let's recall that, according to the Triangle Midsegment Theorem, the length of a midsegment QR will be half of the side length of this triangle.
