(a) Find the values ofxandythat maximize

z=7x+3y,

subject to the following constraints.

x	+	4y		220
x	+	2y		120
x	+	y		100

x0,y0

The maximum value isz= Answer here

(x,y) = Answer here

(b) Replace the constraint x+ 4y220 with x+ 4y230.

The maximum value isz= Answer here (x,y) = Answer here

UNCHANGED

(c) Replace the constraint x+y100 with x+y118.

The maximum value isz= Answer Here

(x,y) = Answer Here

CHANGED

.