write the equation of a line that contains the point (-7,-2) and has an undefined slope.

Question

write the equation of a line that contains the point (-7,-2) and has an undefined slope.

Answer 1

Remember "rise over run"? If every slope is a fraction, then the rise (or y-values) is your numerator and the run (or x-values) is your denominator. For example, slope=3/2 rises 3 units and goes right 2 units.

An undefined slope can be thought of as a fraction, which is also a division problem. There must be a zero in there somewhere. So the question becomes: is the slope 7/0 or 0/7? Well, 0 divided by 7 renders the answer: 0. But 7 cannot be divided by 0 - what can you multiply 0 by to get 7? Nothing. Its solution is undefined.

If our slope, then, has a rise of 7 and a run of 0, then we see that the graph will be a vertical line.

We know that the vertical line passes through (-7, -2) on your graph. It can never pass through any x-value other than x=-7, though it can pass through infinite y-values.

So you're answer is x=-7.

Answer 2

Undefined slope means that the line is vertical, so an equation with x being a fixed value would satisfy that requirement. The only equation that is both vertical and goes through (-7, -2) is x = -7.

Answer 3

x = -7