Question

Write an equation of the line that passes through (8, 3) and (4, 3).

Answer 1

Since the y coordinates are both equal to 3, the equation is y = 3


This is a horizontal line passing through 3 on the y-axis

Answer 2

Will you explain to me how to figure this out?

Answer 3

sure

Answer 4

Because I have several of these questions, and I want to understand how to do them

Answer 5

sure just post them to the left or you can ask here

Answer 6

Here is one that I dont understand -- Write the equation of the line that passes through (-4, 12) and (7, 23).

Answer 7

ok one sec

Answer 8

k

Answer 9

step 1 is to find the slope, how do we do that?

Answer 10

Don't you subtract 7 from -4 and 23 from 12?

Answer 11

yes and you divide those differences, which is the order we divide?

Answer 12

so what do you get when you do the subtractions?

Answer 13

When you subtract 7 - (-4) = 11 and 23-12= 11 ?

Answer 14

Good

Answer 15

Now you divide these differences, what value goes on top?

Answer 16

When you divide it you get 1

Answer 17

actually in this case, it doesn't matter, but it's important to know which value goes on top

Answer 18

yes, the result is 1

Answer 19

so the slope is 1

Answer 20

so m = 1 and we can plug that into y = mx+b to get y = 1x+b or just y = x+b

Answer 21

now we can use any of the two points to find the value of b


So say we use (7, 23), this means that x = 7 and y = 23


So y = x+b becomes 23 = 7+b and solving for b gets us: b = 16


So the equation of the line is y = x+16

Answer 22

I think I have a good understanding, thank you very much

Answer 23

np

Answer 24

But hey, would you solve this problem the same way ? Write an equation in slope-intercept form of the line with an x-intercept of 6 and a y-intercept of 5.

Answer 25

when they say "x-intercept of 6 and a y-intercept of 5", they mean that this line goes through the points (6, 0) and (0,5)

Answer 26

so yes, you can use the same technique to solve this one

Answer 27

So i think I figured it out, but would my answer have 5/6 in it?

Answer 28

more like -5/6, but you probably lost a minus sign somewhere

Answer 29

that's the slope of course

Answer 30

I found my mistake(:

Answer 31

Thanks for being so helpful.

Answer 32

yw