Respuesta :

Answer:

x = 7

Step-by-step explanation:

Given the equations

2x + 3y = 17 → (1)

2y + z = 1 → (2)

5x + 10z = 25 → (3)

Rearrange (2) expressing z in terms of y

z = 1 - 2y

Substitute z = 1 - 2y into (3)

5x + 10(1 - 2y) = 25

5x + 10 - 20y = 25 ( subtract 10 from both sides )

5x - 20y = 15 → (4)

Multiply (1) by 20 and (4) by 3, then add to eliminate the y- term

40x + 60y = 340 → (5)

15x - 60y = 45 → (6)

Add (5) and (6) term by term to eliminate y, that is

55x = 385 ( divide both sides by 55 )

x = 7

Answer:

[tex]x = 7[/tex]

Step-by-step explanation:

From the equation [tex]2y + z = 1[/tex] , we can separate [tex]z[/tex] so that [tex]z = 1-2y[/tex].

The equation [tex]5x+10z = 25[/tex] can then be turned into:

[tex]5x+10(1-2y) = 25[/tex]

[tex]5x+10-20y = 25[/tex]

[tex]5x -20y = 15[/tex]

[tex]x-4y = 3[/tex] (divide by [tex]5[/tex] on both sides)

We can now use elimination to solve for one of the variable:

[tex]2(x-4y) = 2\times3[/tex] (times 2 to get [tex]2x[/tex] for elimination)

[tex]2x-8y=6[/tex]

[tex]2x+3y-(2x-8y) = 17-6[/tex]

[tex]11y = 11[/tex]

[tex]y = 1[/tex]

Now, we can use substitution to solve for [tex]x[/tex]:

[tex]2x+3y = 17[/tex]

[tex]2x+3 = 17[/tex]

[tex]x = 7[/tex]

Hope this helps :)

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