How many solutions will this system of equations have?

y = 3.5x - 3.5
y = -3.5x + 3.5

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%)

Which graph shows the solution to the system of linear inequalities? y-4t< 4 y

24m^2n+30mn^2+18mn, a sweet challenge!