Question

Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this.
-3x + y = 4
x + 3y = 22
Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this.
-3x + y = 4
x + 3y = 22
@Mathematics

Answer 1

x = 1
y = 7

Answer 2

I don't get how you got that. I've done it like three times and got zero for the first equation and it doesn't sound right

Answer 3

I'll will show you how to solve it. Give me just a few minutes.

Answer 4

okay thank you

Answer 5

Solve one of the equations for either x or y. I chose to solve -3x + y = 4 for y.

-3x + y = 4
-3x + 3x + y = 4 + 3x
y = 4 + 3x

Now you take the value of y which is y = 4 + 3x and substitute that into the other equation and solve for x, like so:

x + 3y = 22
x + 3 (4 + 3x) = 22
x + 12 + 9x = 22
10x + 12 = 22
10x + 12 - 12 = 22 - 12
10x = 10
10x/10 = 10/10
x = 1

Now that you have the value for x you can solve for y in the other equation.

-3x + y = 4
-3(1) + y = 4
-3 + y = 4
-3 + 3 + y = 4 + 3
y = 7

Now check the values of x and y by substituting them into both equations and seeing if they equal out.

-3x + y = 4
-3(1) + 7 = 4
-3 + 7 = 4
4 = 4

x + 3y = 22
1 + 3 (7) = 22
1 + 21 = 22
22 = 22

The solution checks out. So your answer is x = 1 and y = 7

Answer 6

Okay see i had the steps right I just didn't have the one instead i was using a zero and getting myself confused thank you so much for the help

Answer 7

You are very welcome. :)