Final answer:
To calculate the perimeter of John's yard, use the formula P = 2(x + 5) + 2x, which simplifies to P = 4x + 10. Option A) is the correct choice for calculating the perimeter.
Step-by-step explanation:
To find the perimeter of a rectangular yard where the long side is (x + 5) units and the short side is (x) units, we use the formula for the perimeter of a rectangle, P = 2l + 2w, where l is the length and w is the width of the rectangle. The length in this case is the long side of the yard and the width is the short side of the yard. So plugging in the given dimensions, the perimeter P would be P = 2(x + 5) + 2x.
When you distribute the 2 across the terms inside the parentheses and add it to the other term, you get P = 2x + 10 + 2x. Combining like terms gives you P = 4x + 10. Option A) is the correct equation to use to find the perimeter of John's yard.