Question

if 7x+2y-6z = 12 ;x,y and z are positive what is the value of (2+z)/(7x+2y)
A) 1/12
B) 1/6
C) 1/4
D) 5/12
E) 7/12

Answer 1

notice what you get if you add +6z to both sides of the equation
7x + 2y -6z +6z=12+ 6z

(7x+2y)= 12+6z

can you factor 6 out of the expression on the right side of the equation?