1. determine whether the graphs of the given equation are parallel, perpendicular, or neither.

y=-2x+3, 2x+y=7.
a. parallel
b. perpendicular
c. neither

2. determine whether the statement is always, sometimes, or never true.

two line with positive slopes are parallel.
a. always
b. sometimes
c. never

3. determine whether the statement is always, sometimes, or never true.

two lines with the same slope and different y-intercepts are perpendicular.
a. always
b. sometimes
c. never

1. A. parallel, because when you get y by itself it is y=-2x+7,  the two equations have the same slope which means they are parallel.

2. B. sometimes, in order for two lines to be parallel they have to have the same slope so, it is possible that two lines say with a slope of 3, those would be parallel BUT it doesn't always have to have a positive slope for it to be parallel like in question 1. 

3. C. never, If they have the same slope they are parallel despite whatever the y-intercept is.

Ibelieve the total for the tip could be $21.90