EQ. 1: x + y = 8
EQ. 2: 4x-y = 7
Rewrite EQ. 1 as EQ. 3: x = 8-y
Replace x in EQ.2 with EQ. 3:
4(8-y) - y = 7
Use the distributive property:
32 - 4y - y = 7
Combine like terms:
32 - 5y = 7
Subtract 32 from each side:
-5y = -25
Divide both sides by -5
y = -25 / -5
y = 5
Now replace y with 5 in EQ. 3 to solve for X:
x = 8-5
x = 3
The point of intersection is X = 3, Y = 5, which is written as (3,5)
Answer:
Step-by-step explanation:
The correct question should be:
We have been told that all we have to do to get profit is to subtract the cost from revenue.
Revenue = 
Cost <em>= </em>
<em />
<em />
Hence:
Profit = 
Putting it in ordered form:
This is an expression for the profit.
The answer & explanation for this question is given in the attachment below.
Using a system of equations, it is found that the correct option is:
A) 1389x+1660y=787x+1121y.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, considering the amounts in each olympics(1389 men and 787 women participated on the 19th, 1660 men and 1121 women in the 22th), the system is:
A) 1389x+1660y=787x+1121y.
More can be learned about a system of equations at brainly.com/question/24342899
