Question

WILL MEDAL FOR RIGHT ANSWER!

Answer 1

What is the equation of the line that passes through the points (−3, 2) and (−5, 8)?

Answer 2

3x − y = −11
3x + y = 5
x + 3y = 3
3x + y = − 7

Answer 3

First, we need to find the slope!

Answer 4

Do you know how to find the slope?

Answer 5

No. how would i do that?

Answer 6

\(\sf\Large Slope = \frac{\color{blue}{y_2}-\color{red}{y_1}}{\color{green}{x_2}-\color{purple}{x_1}}\)

Where the two points are in the form:

\(\sf\Large (\color{purple}{x_1},\color{red}{y_1})~and~(\color{green}{x_2},\color{blue}{y_2})\)

Answer 7

so i divide them?

Answer 8

You divide the difference of y-values by the difference in x-values.

Answer 9

oh ok

Answer 10

Basically, substitute those points into that formula and we solve for the slope.

Answer 11

ok then what would be next?

Answer 12

What did you get as the slope?

Answer 13

one sec

Answer 14

3?

Answer 15

It should be -3, not positive 3.

Check your work to see where you messed up and we'll continue on right after

Answer 16

i did
2-8/-3--5
then turned
--5 into +5
2-8/-3+5

Answer 17

if that make sense

Answer 18

And then following what you did:

(2-8)/(-3+5)

-6/2

-3

Answer 19

i subtracted wrong

Answer 20

ok so whats next

Answer 21

So, let's write our equation in the form of y = mx + b

where m is the slope
where b is the y-intercept

We already found the slope, and now we have to find the y-intercept.

Answer 22

ok

Answer 23

y = -3x + b

We need to plug in one of the two points they gave us in place of x and y and solve for b.

Let's use the point (-3,2)

That point is in the form of (x,y)

That means x = -3, and y = 2

2 = -3(3) + b

Can you solve for b?

Answer 24

how would i do that?

Answer 25

First multiply.

What is -3 * 3 = ?

Answer 26

-9

Answer 27

would b be 11?

Answer 28

@AbdullahM ?

Answer 29

2 = -9 + b

Rearrange the terms and we get:

2 = b - 9

We need to add 9 on both sides to isolate b.

So, yes, b is 11!

Answer 30

So, now our equation is:

y = -3x + 11

Now, that's not one of your answer choices. To get to your answer we need to rearrange the terms.

Add 3x on both sides and you'll find your answer!

Answer 31

how do I add that on both sides?

Answer 32

for example:

a = b - c

Add c on both sides

a + c = b - c + c

a + c = b

And that's all!

Answer 33

ok

Answer 34

ya I'm still confused

Answer 35

What did you get when you added 3x on both sides?

Answer 36

nothing i still didn't understand to example so i looked up the answer but it gave me 8

Answer 37

ok, let's try this a different way:

y = -3x + 11

Can you subtract 11 on both sides and tell me what you get?

Answer 38

11-y=-3x+11
-11
11-y=-3x

Answer 39

is that right?

Answer 40

y = -3x + 11


Subtract 11 on both sides

y - 11 = -3x + 11 - 11

y - 11 = -3x

Does that make sense to you?

Answer 41

ya but why did you switch the y and 11?

Answer 42

We should always put whatever we are adding/subtracting at the end so that way you don't get confused with the signs.

Answer 43

ok then

Answer 44

Is that the answer because that isn't an option?

Answer 45

No.

Now you need to subtract y on both sides

y - 11 = -3x

y - y - 11 = -3x - y

Simplify it more :)

Answer 46

-11 = -3 x-y ?

Answer 47

We made a mistake!!

Hold on:

2 = -3(-3) + b

Solve for b

2 = 9 + b

b = -7

So, the equation should be:

y = -3x - 7

Now to find your final answer, add 3x on both sides.

So, can you simplify this?

y + 3x = -3x + 3x - 7

Answer 48

3 x+y = -7 !

Answer 49

so it's D

Answer 50

yes?

Answer 51

ya it's right

Answer 52

Correct :)