If the length of the rectangle is 15 units long and the width is 11 units long, how long is the diagonal

18.6 units

Step-by-step explanation:

A rectangle is a four sided shape with 4 perpendicular angles. It has two pairs of parallel sides which are equal in distance: width and length. A diagonal can be drawn between opposite corners that splits the triangle into two equal right triangles. The distance of this diagonal is found using the Pythagorean Theorem a² + b² = c². In the rectangle a = 11 and b = 15. Substitute these values and simplify using a square root operation.

11² + 15² = c²

121 + 225 = c²

346 = c²

√346 = c

18.6 = c