If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is
the slope of k?
(1) k is parallel to the line with equation y = (1-m)x + b +1.
(2) k intersects the line with equation y = 2x + 3 at the point (2, 7).
We have to find slope of K i.e. m.
1) Sufficient: parallel lines have equal slopes. =>m= 1-m => m=1/2
2) Insufficient: 7=2m + b, B is unknown, hence cant calculate m.