Answer:
D.
Explanation:
Just see which point yields the highest value.
f(x,y)=4x-3y
Checking choice A:
(x,y)=(5,0)
f(5,0)=4(5)-3(0)=20-0=20.
Checking choice B:
(x,y)=(4,6)
f(4,6)=4(4)-3(6)=16-18=-2.
Checking choice C:
(x,y)=(7,5)
f(7,5)=4(7)-3(5)=28-15=13.
Checking choice D:
(x,y)=(8,2)
f(8,2)=4(8)-3(2)=32-6=26
Choice D yields the highest value of the points given for our relation f(x,y)=4x-3y.