y=mx+b, Does the line pass thru the negative x axis?
1. m + b > 1
2. mb > 0
we need m and b to find whether the line pass through -ve x axis.
from i: either m and b both +ve or one is +ve and the other one is -ve. also the positive is grater than the absolute value of the -ve one. so not suuf cuz we do not know which is +ve and which is -ve.nsf./
from ii: eithe both -ve or both +ve. nsf/.
from i and ii: both are +ve i,e. the slope is +ve and y intercept is also +ve as well.