i dont get this and need to submit by tonight PLEASE HELPP THANKKS

Based on the dimensions of the shape, the length of PR can be found to be 19.8 units.
The given triangle is an equilateral triangle which means that all the sides are equal.
PR = QR
This means that:
2n + 9 = 7n - 18
Solving for n gives:
7n - 2n = 18 + 9
5n = 27
n = 5.4
The length of PR is therefore:
= 2n + 9
= 2 (5.4) + 9
= 19.8 units
Find out more on equilateral triangles at https://brainly.com/question/2351368
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