Question

would an equation of a line with a slope of 4 and a y-intercept of (o,2) be y=4x+2?

Answer 1

yup

Answer 2

one last question for you, youve been such a big help

Answer 3

whats the equation of a line with a slope of 3/7 and contains the point (3,8)

Answer 4

okay
back to the line equation
y = mx + b
given slope so plug it in

y = (3/7)x + b
now plug in the points
8 = (3/7)3 + b
b = 8 - 9/7 = 47/7

so
y = (3/7)x + 47/7

Answer 5

find the equation of a line that contains the points (3,7) and (12, -4)

Answer 6

lols you said last question
try this one, i'll walk you through it
what do you have to do first?

Answer 7

y=mx+b form?

Answer 8

wait, find the slope first

Answer 9

which would be -11/9

Answer 10

yup to both
how do you find the slope of two points

Answer 11

you got it

Answer 12

now you have the formula

y = mx + b
and you have the slope
and two points, now what?

Answer 13

so as of right now the equation is y=-11/9x+b. you put in the two points in the equation?

Answer 14

since both points are on the line
you can choose either ONE
pick one to put into the equation
it doens't matter which one you use, you'll get the same answer

Answer 15

so i could have 7=(-11/9)(3)+b?

Answer 16

yup

Answer 17

and then you solve for b?

Answer 18

you got it

Answer 19

can you walk me through solving b one more time?

Answer 20

sure
you have
7=(-11/9)(3)+b
multiply the fraction
7 = -11/3 + b
add -11/3 on both sides
b = 7 + 11/3
add
b = 32/3

Answer 21

when i multiplied the fraction i got -3.66. how did you get 11/3?

Answer 22

nevermind. thats the fraction of -3.66

Answer 23

lols you're using a calculator?

-3.66 is the same as -11/3
put that into your calculator

Answer 24

yup

Answer 25

so final equation should be y=-11/3+32/3?

Answer 26

you forgot an x
y=(-11/3)x+32/3
^-- here

Answer 27

okay thank you!

Answer 28

cheers ^_^