I've included all the steps and working out in the attached image.
Ten because 6+4=10. Just work backwards with questions like this
From left to right - (-2,6) (4,1) (-2,5) top (1,-3) bottom (-4,-1) (2,-5)
Just borrow from the 7 and take the 1 to the 2 and that will make it as 12 so then you subtract 12 - 4 and the answer will be 1,180
The first you can multiply first equation by 2, you will get 16x - 12y = - 40, then add first equation to second
16x - 12y - 16x + 7y = - 40 + 30
-5y = - 10
Y= 2;
Then put y to first equation, because it easier.
8x - 2*6=-20
8x = - 8
X= - 1
Answer is x = - 1, y = 2.