How do I solve f(x)=mx+b?I know how to find the slope, m=slope which is rise/run. But how do I determine if a table is a linear graph & what do I do next?

How do I solve f(x)=mx+b?

I know how to find the slope, m=slope which is rise/run. But how do I determine if a table is a linear graph & what do I do next?