Solve the system by the substitution method. 2x-y= -24 x+7y= 3

1 answer:

meriva3 years ago

6 0

2x - y = -24
x + 7y = 3

Solve one equation for a variable and plug the resulting value into the second equation.

x + 7y = 3 Subtract 7y from both sides
x = -7y + 3

Now, plug that x-value into the x of the first equation.

2x - y = -24 Plug in the x-value
2(-7y + 3) - y = 24 Use the Distributive Property
-14y + 6 - y = -24 Combine like terms (-14y and -y)
-15y + 6 = -24 Subtract 6 from both sides
-15y = -30 Divide both sides by 15
y = 2

Next, plug the y-value back into the second equation.

x + 7y = 3 Plug in the y-value
x + 7(2) = 3 Multiply
x + 14 = 3 Subtract 14 from both sides
x = -11

y = 2 and x = -11

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