The solution of the equation \( x-y=10 \) and \( x+y=70 \) is \( \ldots \)
A) \( (40,30) \)
B) (30,40)
C) \( (10,60) \)
D) \( (50,20) \)
Given:
The given pair of equations is \( x-y=10 \) and \( x+y=70 \).
To do:
We have to find the solution of the given system of equations.
Solution:
Adding the given equations, we get,
$(x-y)+(x+y)=10+70$
$x+x-y+y=80$
$2x=80$
$x=\frac{80}{2}$
$x=40$
Substituting $x=40$ in $x+y=70$, we get,
$40+y=70$
$y=70-40$
$y=30$
Therefore, the solution of the given system of equations is $(40, 30)$.
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