7 Hours. 315 divided by 45 equals 7.
Step-by-step explanation:
In order to get the inverse of equation, we will interchange the variables and solve for x and y as follows.

whereas, 
or x = 
Now, on interchanging the variable we will get the equation as follows.


y = 
Answer:
3) C.
4) B.
5) C.
Step-by-step explanation:
4x+2x=180
6x= 180
Divide by 6
X= 30
20 medium and large pumpkins
m ... number of medium pumpkins
l ... number of large pumpkins
20 = m + l
20 = m + (m + 6)
20 = 2 * m + 6
2 * m = 20 - 6
2 * m = 14
m = 7 medium pumpkins
l = 20 - 7 = 13 large pumpkins
Result: Julio bought 13 large pumpkins.