Slope and intercept question

Question

Find the equation of the line that contains the point (15,22)

(15,22) and is parallel to the x x-axis. Write the equation in the form y=mx+b

y=mx+b and identify m

and b

Answer 1

A line parallel to the x-axis (it is called horizontal) has an equation in the form y = k

In this case y = 22.

Answer 2

Slope is defined as, for any 2 points on the line, (change in y)/(change in x). However, if a line is parallel to the x-axis, all points on the line have the same y coordinate, so (change in y) will be zero, thus slope is zero. The y-intercept will have the same y-value as every other point on the line, so m = 0 and b = 22. If those values at plugged into the standard slope-intercept format, the line's equation simplifies to y = 22.