Answer:
qr = 2a + 3b
Explanation:
First, we must calculate the measure of each side based on the perimeter. Since all three sides of an equilateral triangle are equal, we divide the perimeter by 3.


4a + 6b (measure of each side)
Being an equilateral triangle, any middle segment is half the length of any of its sides.
So, the value of qr is:

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