The area of the triangle above will equal one half of a rectangle that is 5 units long and 3 units wide. The area of the triangle is 7.5 units and the area of the rectangle is 15 units
If you follow PEMDAS, and x = 3, then you get 54. As an example, x4 is 12. You change X to 3, then multiply (3)4=12. If you follow the rest of the equation, you get 54.