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How many solutions does this linear system have?
y = 2x - 5
-8x – 4y = -20

1 Answer

4 votes

Answer:

one

Explanation:

The lines have different slopes, so there is 1 solution.

A graphing calculator shows it to be (x, y) = (2.5, 0).

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You know the lines have different slopes because the variables have coefficients with different signs when you put the equations in the same form.

y = 2x -5

y = -2x +5 . . . . . matching the form of the first equation

x has a positive sign in the first equation; negative in the second equation

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2x -y = 5

-8x -4y = -20 . . . . matching the form of the second equation

Variable signs are +- in the first equation and -- in the second equation.

How many solutions does this linear system have? y = 2x - 5 -8x – 4y = -20-example-1
User Steve Chavez
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