Answer :

you have to make an equation that i forgot what was called but you just take
x+y=10 and multiply it by -2 so the y’s can cancel out

so you’ll end up with:

-2x-2y= -20
(+) x+2y=14

you’ll get : x = -6


then you plug in -6 for x, solve for y and your coordinates will be

(-6 , 10)
The point of intersection is the (4,6)

Explanation:

We will find the solution of the two equations.

The two equations are: 
x+y=10..(1)
x+2y=14 ...(ii)
subtracting equation (i) from (ii) we get,

x+2y -x-y = 14-10
y = 4

Now, from (i), x+y = 10
x +4 = 10
x = 10-4
x = 6

Hence, the intersection point is (4,6)