180(x - 1)
A quadrilateral has 4 sides, so 180(3) = 540
80 + 110 + 75 = 265
540 - 265 = 275
Last measurement is 275
hope this helps
Basically I just plugged in g(x) into f(x) and simplified, hope that helps!
Answer: 32.25
Mulitply 10.25 by 3 then add 1.50