<PRE><B>Question 33121</B>
IF YOU KNOW EQNS...STRAIGHT FORWARD APPROACH IS SOLVE FOR THE UNKNOWNS ASSUMING AN EQN.HERE YOU ARE TRYING LINEAR..OK...
FOR -2,1.5......WE GET 
1.5=-2A+B.....FOR THE NEXT PAIR OF 0,0.5
0.5=2*0+B...OR...B=0.5
SO 1.5=-2A+0.5....OR......-2A=1.5-0.5=1....OR...A=-1/2=-0.5
SO EQN.IS 
Y=-0.5X+0.5...NOW TEST THE OTHER PAIRS TO SEE IF THIS IS CORRECT....
-0.5=-0.5*2+0.5=-1+0.5=-0.5...OK
-1.5=-0.5*4+0.5=-2+0.5=-1.5...OK

SO THE EQN.IS LINEAR AND IT IS 
Y=-0.5X+0.5</PRE>