Analysis: Generally speaking, the coordinates of intersection points are the key to solving problems, and equations can be solved. The area of a triangle, look at the picture and find the vertical line and the corresponding bottom. If we can find the right angle, it will be easier. Your topic has no specific data, so you can't see it.

4=2K+B 2=B, so the analytical formula Y=X+2.

△AOC area =1/2 * oc * (the vertical line from A to X axis, that is, the ordinate value of A) =0.5*2*4=4.