Answer: 
Step-by-step explanation:
This is a horizontal line at y = -3. If you want to find it mathematically, you could find the slope (y2-y1)/(x2-x1) and you would get 0 over 5, so you know the slope is zero. Pick either point and substitute the numbers into point-slope formula. I went with (3, -3) and got (y - -3) = 0(x-3). The right side is just 0, and if you subtract three from both sides to isolate y, you get the equation y = -3.
Answer:
5
10
4
7
Step-by-step explanation:
Apply the value of x into the expressions:
3(5) - 10 = 15 - 10
= 5
5² - 15 = 25 - 15
= 10
5(5) - 21 = 25 - 21
= 4
5 + 10 - 8 = 15 - 8
= 7
You bought 5 books for $60 and 2 movies for $30
proportional because 1*5/3*5=5/15
