20 12 how to solve the eighth multiple-choice question in Shantou second model science mathematics?
Known functions can draw an image on the number axis to form a triangle with X= 1 Y=3. Because the maximum value of Z=ax+by is 12, the maximum value of X= 1 Y=3 is brought into the z equation to get a+3b= 12, and then the solution is brought into Y = 2/A+3.