The students in Mr. Sarzoza's Physics class went to an amusement park for
a project. Each student needed an
accelerometer that costs $7.50 and a
ticket to the park that costs $30.00. If
x represents the number of students in
Mr. Sarzoza's class, which equation can
be used to find y, the amount in doilars
spent by Mr. Sarzoza's students?

$7.50x + $30.00x = y and i believe that $37.50x = y, works as well, if you don't see the first one.

Step-by-step explanation:

Since each student needs both a ticket and a accelerometer, you put the variable after each of the numbers. And since you need to find the total, you put an addition sign and y after the equals sign. Hope this helps :)

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15