Solve for x and y

5x + 3y = 7

y = 4

Answer: x = - 1 y = 4

Step-by-step explanation:

We are going to solve this using substitution.

Here is the work ...

5x+3 (4) = 7

That is what it woud look like because y is equal to 4.

3 times 4 is 12.

So now we have ...

5x+12=7

Now we want to get All the common factors together ...

To do this we will subtract 12 from 7 and we get - 5.

Here is our equation now ...

5x=-5

Now we divide x by 5 to get x alone, but we also divide - 5 by 5.

x=-1

Now all we have to do to solve for y is put x in an equation.

In this case here is what we will do ...

5 (-1) + 3y=7

Multiply ...

-5+3y=7

Now we need to get the common factors together so lets add 5 to 7.

3y=12

3y/3=y

12/3=y

y=4

But that is already in your problem ... OOF. Dont worry its still correct.