Answer:
about 35.4 yards
Explanation:
Make use of the formula for the area of a square and solve for the side length. The area (A) of a square of side length s is given by ...
A = s²
You are given A and asked to find s. So you have
1255 yd² = s²
To find s, you take the square root of both sides of the equation.
√(1255 yd²) = √(s²)
35.426 yd ≈ s . . . . . the square root of 1255 is irrational, so we have shown an approximation rounded to 3 decimal places.
Each side of the field is about 35.4 yards long.
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Any scientific or graphing calculator can compute the square root for you, as can any spreadsheet program or any of a number of on-line calculators. A Google or Bing search box will also compute the square root for you. (see attachment)