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.
The answer is 2√3
I hope this answers your question :)
Answer:
a)
b)
Step-by-step explanation:
From the question we are told that:
Number Teachers 
Number Student 
Number in committee 
a) Generally the equation for exactly 3 students on the committee is mathematically given by



b) Generally the equation for at least one teacher and at least one student on the committee is mathematically given by
Total Ways-(no of ways of selection no teacher or student)
Where total Ways


Therefore



3x-y/3=b, you are isolating b to the other side