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Solve the system of linear equations by substitution 12x+y=−4 y=2x+16

User Sera
by
6.2k points

1 Answer

1 vote

Answer:

Your solution is (-10/7, 92/7)

Explanation:

12x + y = -4

y = 2x + 16

To use substitution, we want to plug one variable's equation into the other equation.

We can see that y is already solved for us. Plug y into the first equation.

12x + y = -4

12x + (2x + 16) = -4

Combine like terms.

14x + 16 = -4

Subtract 16 from both sides.

14x = -20

Divide both sides by 14.

x = -20/14

x = -10/7

Now that we know x, we will plug it into one of the other equations.

y = 2x + 16

y = 2(-10/7) + 16

Multiply.

y = -20/7 + 16

Add.

y = -20/7 + 112/7

y = 92/7

Your solution is (-10/7, 92/7)

Hope this helps!

User Putnam
by
6.4k points