Question

What is the equation of the line that passes through the points [1/2,-1] and (1,1)?

Answer 1

are you familiar with the equation for slope?

Answer 2

y=mx+b?

Answer 3

no, that's slope-intercept form.

Answer 4

so, do you know the formula for slope?

Answer 5

no

Answer 6

ok, it's (y2-y1)/(x2-x2)

Answer 7

oh now i remember thanx!!!

Answer 8

so you know what to do now

Answer 9

??

Answer 10

more or less

Answer 11

what is still confusing? (even to a small degree)

Answer 12

my answer was y=1/2 but it was not one of my answer options

Answer 13

Please elaborate. Y=1/2 is a horizontal line.

Answer 14

A.
y = 1
B.
y=1/4x+3/4
C.
y = 4x + 3
D.
y = 4x – 3

Answer 15

Firstly, tell me how you found the slope.

Answer 16

1-(-1)/1-1/2

Answer 17

it's upside down, you did x2-x1 on top. it should be on the bottom.

Answer 18

\[(y2-y1)/(x2-x1)\]

Answer 19

dont get it

Answer 20

@superdavesuper

Answer 21

ok, take your given two points: (1/2,-1) and (1,1). Think about what an ordered pair is: an x, paired with a y, and restated as "(x,y). So, take the second given point, and it becomes (x2,y2). Whereas the first pair stays as (x1,y1)

Answer 22

so put the two y's, and the two x's into the formula I gave you.

Answer 23

\(\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
&({\color{red}{ \frac{1}{2}}}\quad ,&{\color{blue}{ -1}})\quad &({\color{red}{ 1}}\quad ,&{\color{blue}{ 1}})
\end{array}
\\\quad \\

slope = {\color{green}{ }}= \cfrac{rise}{run} \implies \cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}
\\ \quad \\

y-y_1={\color{green} m}(x-x_1)\quad \textit{plug in your values and solve for "y"}\)

Answer 24

keep in mind that for the point-slope form, that is \(\bf y-y_1={\color{green} m}(x-x_1)\) you can use either point, \(\bf (x_1,y_1) \ or \ (x_2,y_2)\)

Answer 25

is it a y=1? tht was my answer

Answer 26

dunno.. what did you get for the slope? \(\bf slope = {\color{green}{ m}}= \cfrac{rise}{run} \implies \cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}\)

Answer 27

1/2

Answer 28

y intercept was 2

Answer 29

D?

Answer 30

Show me your process for finding the slope.

Answer 31

got a bit .lagged... one sec

Answer 32

\(\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
&({\color{red}{ \frac{1}{2}}}\quad ,&{\color{blue}{ -1}})\quad &({\color{red}{ 1}}\quad ,&{\color{blue}{ 1}})
\end{array}
\\\quad \\
slope = {\color{green}{ m}}= \cfrac{rise}{run} \implies

\cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}\implies

\cfrac{{\color{blue}{ 1}}-{\color{blue}{ (-1)}}}{{\color{red}{ 1}}-{\color{red}{ \frac{1}{2}}}}\)

Answer 33

\(\bf \cfrac{{\color{blue}{ 1}}-{\color{blue}{ (-1)}}}{{\color{red}{ 1}}-{\color{red}{ \frac{1}{2}}}}\implies \cfrac{2}{\frac{1}{2}}\\ \quad \\
\textit{recall that }\cfrac{\quad \frac{a}{b}\quad }{\frac{c}{d}}\implies \cfrac{a}{b}\cdot \cfrac{d}{c}\qquad thus\\ \quad \\

\cfrac{2}{\frac{1}{2}}\implies \cfrac{\frac{2}{1}}{\frac{1}{2}}\implies \cfrac{2}{1}\cdot \cfrac{2}{1}\)