Solution 2.2:6d

From Förberedande kurs i matematik 1

At the point where the lines cut each other, we have a point that lies on both lines and which must therefore satisfy the equations of both lines:

x+y+1=0 and x=12.

We obtain the solution to this system of equations by substituting x=12 into the first equation

12+y+1=0  y=−13

which gives us the point of intersection as 12−13 .