Intersection of two lines

Find where the two lines y=2x1y = 2x - 1 and y=x+5y = -x + 5 meet. At the meeting point the two yy values are equal, so 2x1=x+52x - 1 = -x + 5. This gives 3x=63x = 6, that is x=2x = 2. Substituting back, y=221=3y = 2 \cdot 2 - 1 = 3. So the intersection is (2,3)(2, 3), marked by the large dot on the graph.