Answer:
x = 10
Step-by-step explanation:
Perimeter of a triangle = the sum of the three sided of the triangle.
In an isosceles triangle, there are two equal sides and a base.
Perimeter = ( 3x - 6) + (3x - 6) + x
58 = 7x - 12
58 + 12 = 7x
70 = 7x
[tex]\frac{70}{7} = \frac{7x}{7}[/tex]
10 = x
