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 :)
