What do the following two equations represent?

y + 1 = -4(x-2)

2x - 8y = 16

same line
distinct parallel lines
perpendicular lines
Intersecting, but not perpendicular lines

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%)