Answer: A. 7x + 3
Concept:
Here, we need to know how to find the perimeter of a triangle
Perimeter (triangle) = s₁ + s₂ + s₃
s₁ = side one
s₂ = side two
s₃ = side three
Solve:
Given information
s₁ = 3x
s₂ = 3x + 3
s₃ = x
Given expression
P = s₁ + s₂ + s₃
Substitute values into the expression
P = (3x) + (3x + 3) + (x)
Combine like terms
P = (3x + 3x + x) + (3)
P = (6x + x) + 3
Hope this helps!! :)
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