The cost of meal = 
The tip to the waiter =
%
Discount =
%
Cost = 
Cost = 
Cost = $
0
For this case we have the following system of equations:

We can write a system of equivalent equations.
For this, it is enough to multiply one of the two equations by a scalar.
Multiplying the equation 1 by 2, we have:

Therefore, the new system of equations is:

Answer:
A system that is equivalent is:
D) 
If you have

as your cost,
and you paid

,
then

.
Thankfully, most cellphone companies don't charge for minutes anymore!
Answer:
He will read 92 pages in an hour going by the current rate at which he reads
Step-by-step explanation:
The complete question is as follows;
Jamil found that he reads 1/5 of his 115 - page book in 1/4 of an hour. At this rate how many pages does he read in an hour
We proceed as follows;
If he reads 1/5 of 115 in 1/4 hour
1/5 of 115 pages refer to 1/5 * 115 = 23 pages
This means that he reads 23 pages in quarter of an hour
So in an hours the number of pages he will read will be 23 * 4 = 92 pages