Answer:
-7
Step-by-step explanation:
3x +17 + 5x = 7x +10
3x +17 + 5x - 7x = +10-17
x=-7
We first must calculate how many ways 2 oblects can be chosen from 5.
combinations = 5! / 2! * (5-2)!
combinations = 5*4 / 2
combinations = 10
There are 10 ways to choose the 2 buttons and 5 ways to choose the final butto so there are 10 * 5 = 50 different ways.
Source
1728.com/combinat.htm
We will traduce the sentences into equations.
Let x be the number of hours in the first job, and y be the number of hours in the second job.
Then the equations are:

The above system has many solution, we can select for example:
x = 1, y = 16. So we can work one hour at the first job and 16 hour at the second job.
I believe the answer is 27/30
The zeros are 3 and -5. Hope this helps!