If we have the equation of a line: y=ax+b
How to find a if with only the x-intercepts (called m) and y-intercepts (called n)
+ First we have y=0 and x=m or 0=a*m+b or b= -a*m
+ Then we have x=0, y=n or n=a*0+b or b=n
And if m≠0 we have a= -n/m
and if m=0 this line has no slope
