paralell lines have same slope
paralell to x axis means slope of x axis=slope of line
slopt of x axis=rise/run, rise=0, run=infinity, so slope=0
y=mx+b
m=slope
if m=0,
y=0x+b
y=b
therefor the answer is an equation that is y=constant where there is no x
answer is 2) y=10
