Question

Can someone help explain what a linear equation is? Please give an example.

Answer 1

y=mx+b is a linear equation; represents a line,

Answer 2

y=x is an example

Answer 3

but what do i need to use it for...like how do i know that the question is asking me for that?

Answer 4

y = (f(c))x + c is linear as well

Answer 5

what type of question?

Answer 6

A question that involves lines and planes

Answer 7

on a graph

Answer 8

linear equations are easy to deal with, which is why we try to get the harder stuff into linear form

Answer 9

your going to have to be more specific with a question :)

Answer 10

ok wait....im going to give you a question and help explain it plz...one sec

Answer 11

Write the equation for the line passing through the points (-3, 3) and (0, -3).

Answer 12

when given 2 points; we can draw a line between them right?

Answer 13

yea im pretty sure...thats all the question says and then it shows a graph

Answer 14

the most basic thing to do with 2 points is to determine the slope between them; this is a very important measurement to have

Answer 15

it is the distance and direction that y changes when compared to the distance and direction that x changes

Answer 16

http://www.google.com/#hl=en&cp=8&gs_id=s&xhr=t&q=linear+equations&qe=bGluZWFyIGU&qesig=oExNk1mLH4SZDXjXtRTaNQ&pkc=AFgZ2tnhzOtomuk8Ja4zcdv1rXe4

Answer 17

yea i think that slope is rise over run but can u put the y=mx+b thing into use with the coordinates i gave?

Answer 18

given (-3, 3) , (0, -3).

y moves from 3 to -3; a distance and direction of -6, right?

x moves from -3 to 0; a distance and direction of 3, would you agree?

Answer 19

yes?

Answer 20

Given the two points \((x_1,y_1)\) and \((x_2,y_2)\)
\[m = \frac{y_2 - y_1}{x_2 - x_1}\]\[y_1 = mx_1 + b\]Solve for \(b\)

Answer 21

make sure if done the math right :)

Answer 22

how do i solve for b?

Answer 23

the slope then is defines as:

the distance and direction of y
------------------------- = -6/3
the distance and direction of x

we tend to write the slope in reduced form tho

slope = -6/3 = -2 do you agree?

Answer 24

Solve slope equation, then plugin \(m, x_1, y_1\)

Answer 25

ok so can u plug it in so i can see how to do it?

Answer 26

we are working up to that i believe

Answer 27

ok so can u plug it in so i can see how to do it?

Answer 28

ok

Answer 29

im confused...

Answer 30

an easy way to solve for y = mx + b ; given any point and knoing the slope is to simply use a point given and solve for b

y = mx + b
-mx -mx
---------------
y-mx = b

Answer 31

\[(x_1,y_1) = (-3, 3)\]\[(x_2,y_2) = (0, -3)\]\[m = \frac {(-3) - (3)}{(0) - (-3)}\]\[3 = \frac {(-3) - (3)}{(0) - (-3)}(-3) + b\]

Answer 32

so subtract mx from both sides then what?

Answer 33

( x, y)
(-3,0)

0 - (-2)(-3) = b

b = -6

Answer 34

fill in your slope, y and x to solve for b; then rewrite the formula with the information

Answer 35

y = mx + b

y = -2x -6

Answer 36

what does each variable represent?

Answer 37

y is a generic variable for any given point

x is also a generic variable for any given point

m is the slope that was found

and b is also known as the yintercept

Answer 38

the y intercept is the point in which a line crosses it right?

Answer 39

cross the y axis that is

Answer 40

yep; think of the line as the path of a football and the y axis catches, or intercepts it

Answer 41

x intercept is the same concept :)

Answer 42

haha now ur talking my language...thx...im gonna post some more specific questions later ;)

Answer 43

good luck with them :)

Answer 44

yea but it would be good if u answered them cuz u actually made me understand

Answer 45

Given two points \((x_1, y_1)\) and \((x_2, y_2)\)
\[m = \frac{y_2 - y_1}{x_2 - x_1}\]\[y_1 = mx_1 + b\]
So we have:
\[(x_1,y_1) = (-3, 3)\]\[(x_2,y_2) = (0, -3)\]\[m = \frac {(-3) - (3)}{(0) - (-3)} = -2\]\[3 = \frac {(-3) - (3)}{(0) - (-3)}(-3) + b\]\[b = 3 -\frac {(-3) - (3)}{(0) - (-3)}(-3)\]\[b = 3 - (-2)(-3) = 3 - 6 = -3\]

Amistre64: Your intercept value was wrong.

Answer 46

Finally: the equation for the line is:\[y= -2x - 3\]

Answer 47

... well its right for the dyslexic point I used :)