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Solve the system of equations using substitution

6x-y=68

2y=x

the solution is

User Datasert
by
6.1k points

1 Answer

5 votes

Answer:

x = 136/11 , y = 68/11

Explanation:

Solve the following system:

{6 x - y = 68

2 y = x

Hint: | Choose an equation and a variable to solve for.

In the second equation, look to solve for x:

{6 x - y = 68

2 y = x

Hint: | Reverse the equality in 2 y = x in order to isolate x to the left hand side.

2 y = x is equivalent to x = 2 y:

{6 x - y = 68

x = 2 y

Hint: | Perform a substitution.

Substitute x = 2 y into the first equation:

{11 y = 68

x = 2 y

Hint: | Choose an equation and a variable to solve for.

In the first equation, look to solve for y:

{11 y = 68

x = 2 y

Hint: | Solve for y.

Divide both sides by 11:

{y = 68/11

x = 2 y

Hint: | Perform a back substitution.

Substitute y = 68/11 into the second equation:

{y = 68/11

x = 136/11

Hint: | Sort results.

Collect results in alphabetical order:

Answer: {x = 136/11 , y = 68/11

User Ben Whaley
by
6.1k points