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4 votes
I'm stuck on algebra.

First, write three (3) equations of lines in the following
forms: a) point-slope form, b) slope-intercept form, and c) standard form. Next, choose
another form to write each equation in, and then show all the steps required to convert each
equation to the other form.

2 Answers

7 votes
point slope form : y-y1 = m(x-x1)
slope intercept form : m=(y-y1)/(x-x1)
standard form : Ax + By = C

just pick any random points on a graph and plug the same points into all three forms.
User Sunney
by
5.3k points
5 votes

Algebra is tougher when they make you make up your own problems like this.

Point slope form: That's a line through point (a,b) with slope m,

y - b = m(x-a)

Let's pick point (2,-3) and slope 7,

y + 3 = 7(x-2)

Slope-intercept form: That's a line given slope m and y intercept b,

y = mx + b

We'll pick slope m=3 and y intercept -2:

y = 3x - 2

Standard form: That's ax+by=c or sometimes ax+by+c=0; standard form isn't standard. We'll go with the former, picking some random numbers for a,b,c;

4x - 3y = 5

Let's write all three equations in all three forms

y + 3 = 7(x-2) point/slope

y = 7x - 14 - 3

y = 7x - 17 slope/intercept

7x - y = 17 standard

~~~~~~~~~~

y = 3x - 2 slope/intercept

y + 2 = 3x point/slope

3x - y = 2 standard

~~~~~~~~~~~~~~~

4x - 3y = 5 standard

3y = 4x - 5

y = (4/3) x - (5/3) slope/intercept

y + 5/3 = (4/3) x point/slope

User Nathan Furnal
by
5.6k points