## Introductory Algebra for College Students (7th Edition)

The perimeter of the rectangle is $10x$.
We know that the perimeter of a rectangle can be given by the formula: $$P = 2l + 2w$$ Let's plug in $x$ for the width and $4x$ for the length: $$P = 2(4x) + 2(x)$$ We simplify to get: $$P = 8x + 2x$$ We then combine like terms: $$P = 10x$$ The perimeter of the rectangle is $10x$.