Can anyone help me on this expression triangle

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.

How many glue sticks are in a basket containing 96 scissors, if the ratio of glue sticks to scissors is 19 to 57.

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)