First of all, I'm going to assume that we have a concave down parabola, because the stream of water is subjected to gravity.
If we need the vertex to be at
, the equation will contain a
term.
If we start with
we have a parabola, concave down, with vertex at
and a maximum of 0.
So, if we add 7, we will translate the function vertically up 7 units, so that the new maximum will be 
We have

Now we only have to fix the fact that this parabola doesn't land at
, because our parabola is too "narrow". We can work on that by multiplying the squared parenthesis by a certain coefficient: we want

such that:
Plugging these values gets us

As you can see in the attached figure, the parabola we get satisfies all the requests.
140 divided by 14 is 10. So x is 10. And Y is 140. 140 divided by y (1) =140
Plugging in (2,-7) into
y=-5x+b, we get that b=3.
Therefore, the equation is y=-5x+3
Answer: Required expression = 8h +3.50
Emilia's job pay $ 43.5 in a day when she works 5 hours.
Step-by-step explanation:
Given: Hourly earning = $8.00
gas allowance per day = $3.50
Pay per day = (Hourly earning ) x (Number of hours ) + (gas allowance per day)
Let h = number of hours
Pay per day = 8h +3.50
If Emily worked for 5 hours, then put h= 5, we get
Pay per day = 8(5) +3.50
= $ 40 +3.50
= $ 43.5
Required expression = 8h +3.50
Emilia's job pay $ 43.5 in a day when she works 5 hours.