Question

What is the standard form equation of the line passing through (1, –5) with a slope of –1?

Answer 1

What form do you know? Maybe start with the point-slope?

Answer 2

what is the point slope form?

Answer 3

I'll take that as a "no". This is not good at all. You are given a point and the slope. Why would you not be given the Point-Slope form of a line FIRST?!

What forms do you know?

Answer 4

Is the point slope form y=mx+b? thats all i know now. and i know how to find the slope. which im already given

Answer 5

y = mx + b

This is the Slope-Intercept form. This is very useful, but it is not quite what we need for this one.

Let's see if we can figure it out.

Point:(1,-5)
Slope: -1

Can we use this information to find the y-intercept?

y-intercept: (0,What)

Answer 6

We cant use that to find that, ahh so the point slope form is y-y^1 = m(x-x^1)

Answer 7

That is it, but subscripts, of course.

Slope: m = -1
Point: (1,-5) gives x1 = 1 and y1 = -5

Fill in the blanks.

Answer 8

We could also have simply substituted.

Given y = mx + b,
We have m = -1, x = 1, and y = -5, thus:

-5 = (-1)(1) + b and we can solve for b.

You need Standard Form. You wouldn't happen to know that one, would you?

Answer 9

-4=b, correct? I dont know what standard form is but where did you get that 1 in (-1)(1) from?

Answer 10

ax + by = c is standard form?

Answer 11

(-1)(1) are the substitutions of m = -1 and x = 1 into the term "mx".

With b = -4, we have y = -x - 4. Standard form is x + y = -4.

We just need to learn to recognize the various forms. We also need to get our algebra up to speed so we can fluently change between the various forms.

Answer 12

Yes, I know. I took algebra 1 a few years back and now im taking algebra 2 so I'm obviously a little rusty now.

Answer 13

But thank you so much for your help it refreshed my memory a bit.

Answer 14

Very good. It does seem to be coming back, even in this brief conversation. I think you'll be okay. Just keep getting up to speed.