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6 votes
Solve the system of linear equations by elimination.

3x−30=y
7y−6=3x

please explain

User AMagic
by
6.0k points

2 Answers

7 votes

Answer:


x = 12.y = 6

Explanation:

Restructuring

[3x - 30 = y

-3x - 6 =7y


( - 36)/( - 6) = ( - 6y)/(6)

y=6

Sub 6 in equ II

7(6)-6=3x


(36)/(3) = (3x)/(3)

x=12

User Umar Farooque
by
5.7k points
4 votes

Answer: y = 6; x = 12

Explanation:

3x - 30 = y

Change this into an equation where x and y are in the same side.

3x - 30 = y

Subtract y from both sides

3x - y - 30 = 0

Add 30 to both sides

3x - y = 30

7y - 6 = 3x

Do the same thing I did to the first equation

7y - 6 = 3x

Subtract 3x from both sides

-3x + 7y - 6 = 0

Add 6 to both sides

-3x + 7y = 6

We can now use the system of elimination to find x and y.

3x - y = 30

-3x + 7y = 6

After adding both equations, you get:

6y = 36

Divide 6 from both sides

y = 6

Since we now know y, we can solve for x.

3x - 30 = y

Substitute y for 6

3x - 30 = 6

Add 30 to both sides

3x = 36

Divide both sides by 3

x = 12

Hope this helped!

User Limak
by
5.6k points