Concrete workers are busy preparing to pour a rectangular patio on the rear of Miguel's new house. The workers have laid out, using boards, what appears to be rectangle to frame where the concrete will go. What could the workers do to ensure the patio is really rectangular before pouring the concrete?

See Explanation below.

Step-by-step explanation:

What the workers can do to ensure the patio is truly rectangular, before pouring the concrete, is to measure the length of the sides of the patio.

This requires full knowledge of the physical properties of a rectangle.

The opposite sides of a rectangle (the two sides which go in the same direction or which are parallel to each other) are equal in length and one set of parallel sides must be longer than the other set of parallel sides.

These are the conditions that the patio must satisfy, to be truly rectangular.

Once the workers have made sure of this, they can go ahead and pour the concrete.

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value