Question

PLEASE HELP!!!! 15 POINTS!!!!

Answer 1

124 mm is the longest side

Explanation:

5x + 3 + 7x + 5 + 12x -20 = 276

24x -12 = 276

24x = 288

x = 12

1st side = 5x+3 =5(12)+3=63 mm

2nd side = 7x + 5=7(12) + 5=89 mm

3rd side = 12x -20= 12(12) -20=124 mm