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2 years ago

Solve the system of linear equations by substitution. x+4y=18 y=-x+9

Mathematics

1 answer:

Dima020 [189]2 years ago

6 0

Using the substitution method, the solution to the system of linear equations, is: (6, 3).

<h3>System of Linear Equations</h3>

Using substitution method, we can make one of the variables the subject of the formula for one of the equations, then find the other variable by substituting.

Given:

x + 4y = 18 --> eqn. 1
y = -x+9 --> eqn. 2.

Substitute y = -x + 9 into equation 1.

x + 4(-x + 9) = 18

x - 4x + 36 = 18

-3x + 36 = 18

-3x = 18 - 36

-3x = -18

x = 6

Substitute x = 6 into equation 2 to find y

y = -6 + 9

y = 3

Therefore, using the substitution method, the solution to the system of linear equations, is: (6, 3).

Learn more about system of linear equations on:

brainly.com/question/11767839

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