Question

Which is an equation in point-slope form for the given point and slope?



Point: (–2, 4); Slope: 5



A.


y – 4 = 5(x + 2)


B.


y + 4 = 5(x + 2)


C.


y – 4 = 5(x – 2)


D.


y + 4 = 5x – 10

Answer 1

Equation of line passing through one point is given by:

\(y - y_1 = m(x - x_1)\)

Here \(m\) is the slope and \((x_1, y_1) \) is your given point..

Put m = 5, \(x_1\) = -2 and \(y\) = 4 in above equation..

Go ahead..

Answer 2

Keep \(x\) and \(y\) as such there..

Answer 3

C?

Answer 4

Go through it once more..

Answer 5

Remember, you are given x1 = -2 and not 2...

Answer 6

i dont understand

Answer 7

Put \(x_1\) here..

\(\large x - (x_1)\)

Answer 8

Put value of \(x_1\) in that bracket..

Answer 9

i still dont get it at all. i dont get how you find the answer. it doesnt make sense to me

Answer 10

See you have one minus sign in front of \(x_1\) and \(x_1\) itself contains one minus sign ie

\(\large x - (-2)\)

So, \(-(-)\) becomes \(+\)

It will become : \(y - 4 = 5(x + 2)\)

Answer 11

what does x1 stand for? i dont get it?

Answer 12

\((x_1, y_1)\) is the point from which the given line is passing..

See, you have given this point in your question ie \((-2, 4)\)..

Answer 13

oooh ok. how do i know when to change the sign from minus to plus? like you gave me the equation (x - x1) but you said the answer is (x + 2) ?

Answer 14

i mean you said now -(-) becomes + but i dont see how you came upon that it needed to be changed??

Answer 15

See the equation is by default : (x - x1)

Or you can write it as : (x - (x1)).. Right???

Answer 16

yes

Answer 17

ok i'm gonna try to do a problem on my own, is it ok if you tell me if I get the answer right?

Answer 18

is it C?