How many solutions does this linear system have?

y = 2x – 5

–8x – 4y = –20

one solution: (–2.5, 0)
one solution: (2.5, 0)
no solution
infinite number of solutions

Respuesta :

The solution is (2.5,0)....

Answer:

Option 2 - One solution: (2.5, 0)                  

Step-by-step explanation:

Given : Two linear equation -

Equation 1 - [tex]y = 2x - 5[/tex]

Equation 2 - [tex]-8x - 4y = -20[/tex]

To find : How many solutions does this linear system have?

Solution :

We solve the given equations,

Substitute the value of y from equation 1 in equation 2

[tex]-8x - 4y = -20[/tex]

[tex]-8x - 4(2x-5) = -20[/tex]

[tex]-8x - 8x+20 = -20[/tex]

[tex]-16x=-40[/tex]

[tex]x=\frac{40}{16}[/tex]

[tex]x=2.5[/tex]

Now, put value of x in equation 1

[tex]y = 2x - 5[/tex]

[tex]y = 2(2.5) - 5[/tex]

[tex]y = 5 - 5[/tex]

[tex]y = 0[/tex]

There is one solution (x,y) = (2.5, 0)

Option 2 is correct.

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