3) the line intercepts x=0 with y=-1 and passes through (3,-2) so over 3 x-"steps" it decreased by 1, so it's slope is (-1/3)=-0.333
in standard form the equation of the line is: y=(-1/3)x-1
4) from the entries (-3,16) and (-1, 12) we have an x difference of 2 and y was reduced by 4 so the slope is=-4/2=-2 add this slope to the x=-1 value to get the x=0 value: 12+(-2)=12-2=10 (=y at x=0)
again fill the values into the line standard form: y=-2x+10
