Question

A triangle has side lengths of 2x , x + 4, and 3 (x + 3). Find the value of x if the perimeter of the triangle is 55 inches.​

Answer 1

• 7 inches

Explanation:

Perimeter is the sum of side lengths:

• P = 2x + x + 4 + 3(x + 3)
• P = 55

Solve for x:

• 2x + x + 4 + 3(x + 3) = 55
• 3x + 4 + 3x + 9 = 55
• 6x + 13 = 55
• 6x = 55 - 13
• 6x = 42
• x = 42/6
• x = 7

Answer 2

x=7

Explanation:

55=2x+(x+4)+[3(x+3)]

55=2x+x+4+3x+9

55=6x+13

55-13=6x

42=6x

7=x