I really need this pleaasehelp

The base of a triangle exceeds the height by 7 centimeters. if the area is 400 square centimeters, find the length of the base and the height of the triangle.

Me, prove a quadrilateral with vertices g(1,-1), h(5,1), i(4,3) and j(0,1) is a rectangle using the parallelogram method and a rectangle method.

Which points are solutions to the linear inequality y < 0.5x + 2? check all that apply. (–3, –2) (–2, 1) (–1, –2) (–1, 2) (1, –2) (1, 2)