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Zorluk: KolaySystems of Linear Equations

If the equations x+2y=12x + 2y = 12 and x+y=7x + y = 7 are true for the same values of xx and yy, what is the value of yy?

Cevap: 5

Cevap

The value of yy is 5.
Subtracting the equation x+y=7x + y = 7 from x+2y=12x + 2y = 12 gives (xx)+(2yy)=127(x - x) + (2y - y) = 12 - 7, which simplifies directly to y=5y = 5.

Adım Adım Çözüm

1
Subtract the second equation from the first equation.
y=5y = 5
Subtracting x+y=7x + y = 7 from x+2y=12x + 2y = 12 eliminates the xx terms, leaving a single linear equation in terms of yy.

Anahtar Kavram

Solving systems of linear equations using elimination.
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