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1 vote
Solve by substitution
x+3y=5
-2x-4=-5


1 Answer

7 votes

Answer:

x = 1/2 , y = 3/2

Explanation:

Solve the following system:

{3 y + x = 5

-2 x - 4 = -5

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

In the second equation, look to solve for x:

{3 y + x = 5

-2 x - 4 = -5

Hint: | Isolate terms with x to the left hand side.

Add 4 to both sides:

{3 y + x = 5

-2 x = -1

Hint: | Solve for x.

Divide both sides by -2:

{3 y + x = 5

x = 1/2

Hint: | Perform a substitution.

Substitute x = 1/2 into the first equation:

{3 y + 1/2 = 5

x = 1/2

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

In the first equation, look to solve for y:

{3 y + 1/2 = 5

x = 1/2

Hint: | Isolate terms with y to the left hand side.

Subtract 1/2 from both sides:

{3 y = 9/2

x = 1/2

Hint: | Solve for y.

Divide both sides by 3:

{y = 3/2

x = 1/2

Hint: | Sort results.

Collect results in alphabetical order:

Answer:{x = 1/2 , y = 3/2

User Brownmamba
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