Joseph D. answered • 6d

B.S. Degree in Physics with Tutoring Experience

Hi Riley W.,

We can use y = mx + b to show the line at x = 0 is y = b:

y = m*0 + b

y = b

From this we might see that the line x = 0 in a line on the y-axis.

We can also use the slope m = y/x for the line x = 0:

m = y/0

m = ∞

From this we see Infinite slope that is a vertical line. A vertical line at x = 0 is a line on the y-axis.

For a perpendicular line to an infinite slope we can take the negative reciprocal m = -x/y:

m = -0/y

m = 0

For the point given (3, 1) we can use y - y_{1} = m*( x - x_{1}) with m = 0:

y - 1 = 0*( x - 3)

**y = 1** (the answer)

I hope this helps, Joe.