For what values of x and y must this quadrilateral be a parallelogram? Find the lengths of the sides.
The diagram is not to scale.
9x
2x+4
4y+24
4y

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)