Well to start, we need to combine like terms all the equations together , so n+ 4n+4n = 9n -2-7 = -9 put them together and it’s 9n - 9 the perimeter is 45 so 9n - 9 = 45 +9 +9 —————— 9n = 54 ——————- 9 9 Then the 9 cancels, drop down the n and divide 54/9 and you get
n = 6
and that’s the answer to prove it you can do 4(6) - 2 = 22 4(6) - 7 = 17 + 6 because you just replace the n with 6 Add them... 22+17+6 = 45 and so now we know for sure the value of n is 6!