Question

The coordinates of intersection point of lines $x+y=7$ and $x-y=3$ will be:

• A. $(4,3)$
• B. $(7,1)$
• C. $(5,2)$
• D. $(6,1)$

Answer 1

The correct option is C $(5,2)$

Given:

$x+y=7$ $-Eq.\left(1\right)$

$x-y=3$ $-Eq.\left(2\right)$

To find: coordinates of intersection point i.e. value of $x$ and $y$ satisfying equation $1$ and equation $2$.

Adding $Eq\left(1\right)$ and $Eq\left(2\right)$

$(x+x)+(y-y)=(7+3)$

$2x=10$

$x=\frac{10}{2}=5$

Substituting the value of x in $Eq\left(2\right)$

$5-y=3$

$y=5-3$

$y=2$

So, coordinates of intersection point is $(5,2)$.