Imissed class once in algebra so now i don't understand it. i'd really appreciate it if you me and explained it! !

Explanation:

Pay attention to the slopes of these lines. The slope is the value stuck to x.

How to know if lines are perpendicular:

The slopes are the negative reciprocals of each other. This means that in fraction form, their top and bottom are switched, and their sign changes from pos-->neg or neg-->pos.

Ex of perpendicular lines:

y = 3x + 2   AND  y = -1/3 x + 4

y = 2/3x + 1  AND  y = -3/2x + 1

Not perpendicular example: y = 3x + 1; y = 1/3x + 2 because sign not changed.

How to know if lines are parallel:

The slopes are the same.

Ex: y = 5x + 12 is parallel to y = 5x + 300

SPOILERS

In the question given to you:

Lines a and c are parallel because they have the same slope, 8.

Line b is not perpendicular to a and c because its slope sign is not negative to a and c.

66.666666667%

step-by-step explanation:

divide 150 by 100

divide 100 by 1.5

there you go!

decreased by 33.333333334%