The variables are actually m. we are doing variables on each side and its very confusing!! :(

In what form is the following linear equation written y=9x+2

Which shows the first equation written in slope-intercept form? 1/2 (2y + 10) = 7x

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%)