Determine which of the lines, if any, are parallel or perpendicular. Explain. 9. The lines pass through the following points:
Line a: (1, 5) and (-2, -4)
Line b: (3, 2) and (1, -4)
Line c: (6, 1) and (-4, 2)

10.
Line a: 4y - 12x = 20
Line b: 3y = -x + 2
Line c: y = 3x - 1

Pls me this is due today and i need i will make brainliest if you me answer correctly and i will report if you try to give me a dumb answer.

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?