What does equilateral triangle mean

The polygon tool to draw a rectangle with a length of 5 units and a height of 3 units. one of the sides of the rectangle falls on line ab , and the rectangle has a vertex of a. each segment on the grid represents 1 unit.

What is f(3) for the quadratic function f(x)= 2x^2+ + x - 12

Given right triangle xyz, which correctly describes the locations of the sides in relation to