Question

Solve the system of linear equations by substitution.

x−y=5
x+3y=9






Question
Solve the system of linear equations by elimination.

x+4y=6
−x−2y=−4

Answer 1

Solve one of the equations for one of the variables in terms of the other. Let's solve the first equation for x:

x - y = 5

x = y + 5

Substitute the expression for the variable into the other equation, and solve for the remaining variable.

x + 3y = 9

(y + 5) + 3y = 9

4y + 5 = 9

4y = 4

y = 1

Substitute the value found for y back into one of the original equations and solve for the other variable. Let's use the first equation:

x - y = 5

x - 1 = 5

x = 6

Therefore, the solution to the system of linear equations is x = 6, y = 1.