Answer:
x = 11
Step-by-step explanation:
if the perimeters are equal then:
the perimeter of the first triangle : 3x + 9 + 3x + 3x + 8 = 9x + 17
the perimeter of the second triangle : 3x + 3x + 4x + 6 = 10x + 6 and
9x + 17 = 10x + 6 export like terms to the same side of the equation
17 - 6 = 10x - 9x
11 = x
we can find the lengths by replacing x with 11 in given expressions.
