Question

FAN AND MEDAL

Answer 1

Write the equation of the line that is parallel to the line y = −3x + 12 and passes through the point (−1, 6).
Choose one answer.
a. y = one thirdx + 7
b. y = −3x + 3
c. y = one thirdx + 3
d. y = −3x + 7

Answer 2

The gradient is equal to -3 since they are parallel.

Answer 3

You are given a coordinate of a point where the line passes. So any idea?

Answer 4

Hmm
What would my first step be?

Answer 5

Pretty confused with this

Answer 6

m - gradient
c - intercept

Answer 7

ok youre first step would be to look at the slope/gradient. the standard formula for a straight line is y = mx +b where m is the slope/gradient. For a straight line to be parallel to another the two lines must have the same slope. In this case you are looking for a slope of -3 or something in the form of y = -3x +b. That means two of the answers are completely wrong. the next step is to take the point given (-1,6) (x,y) and plug them in to corresponding x and y values in the equation the remaining answers and see if they work meaning if you plug in -1 for x into the equation do you come out with 6 for the y value.

Answer 8

ok so it would be b or d?

Answer 9

@Rhystic Nicely explained. :)

Answer 10

@kyle55 Plug a value and check whether you get 6 for y.

Answer 11

whts the equation?

Answer 12

y= -3x + 3?

Answer 13

Try both of them (b and d). Plug -1 for x and see whether you get 6 for y. If it does it's the equation. :)

Answer 14

Correct!

Answer 15

6= -3(-1) + 3 ?

Answer 16

yeah

Answer 17

6=4 + 3
so that is not the answer?

Answer 18

That's the equation of the line parallel to y=-3x+12

Answer 19

-3 * -1 = +3

Answer 20

Not sure i understand quite yet

Answer 21

Am I wrong @Aureyliant ? :)

Answer 22

Everything looks correct… Although not sure because I didn't check the overall problem's answer.

Answer 23

@Aureyliant Can you explain it to kyle?

Answer 24

Kyle what part didn't you understand?

Answer 25

I got lost somewhere in the middle. Can you start from the beggining and work it out for me?

Answer 26

y = mx+c is the general form of a straight line equation where m is the gradient of the line and c is the intercept.

Answer 27

You are given the coordinates of a point where the new line should pass.

Answer 28

alright

Answer 29

then we plug the options in?

Answer 30

Since the gradient is equal to -3 there are two answers (b and d). The line should also go through the point (-1,6). So if we plug x=-1 for one of the two equations, the one that gets y=6 is the answer.

Answer 31

so
b. y = −3x + 3

Answer 32

i plug -1 into x and 6 into y
?

Answer 33

You don't plug in a value for y. You need to only substitute -1 for x. If you get y=6 for the answer, then that's equation of the line satisfying the above conditions.

Answer 34

thats what i was confused wit i thinkh

Answer 35

so b is the answer

Answer 36

no you just use the x value and see what number comes out for y if that number matches the y coordinate that you are given then it is correct. for example in this case the correct answer is b. you are given y = -3x +3 and coordinate (-1,6) you use the x value (-1) in the equation: y= -3*-1+3 and see if you get 6 if you do then that equation has a line passing through the coordinate you need.

Answer 37

thank you for the help

Answer 38

Did you understand it?

Answer 39

Yes, i was confused about where to plug everything in. Should i ask another question to make sure i got it?

Answer 40

Ok go ahead. :)