Question

Show me how to do this​

Answer 1

x = 7 cm

Explanation:

The perimeter of the given triangle:

P = (2x + 1) + (x + 2) + (3x - 9) and P = 36 cm.

Therefore we have the equation:

2x + 1 + x + 2 + 3x - 9 = 36 combine like terms

(2x + x + 3x) + (1 + 2 - 9) = 36

6x - 6 = 36 add 6 to both sides

6x = 42 divide both sides by 6

x = 7