Question

What is an equation of the line, in point-slope form, that passes through the given point and has the given slope?
point: (8, –8); slope: 3


y – 8 = 3 (x + 8)
y + 8 = 3 (x + 8)
y – 8 = 3 (x – 8)
y + 8 = 3 (x – 8)

Answer 1

ok so if you have a point (x1,y1) and a slope m
the corresponding line equation is given by

y = y1 + m(x-x1)

can you do it now ?

Answer 2

So, would it look like this

y= -8+3(x-8) ?

Answer 3

So, it would be the 1st one . Right?

Answer 4

no .. notice that you have y = -8 +3(x-8)
in order to bring it to the form of your options you have to add 8 to both sides

what do you get ?

Answer 5

I don't understand how to write it out ?

Answer 6

y = -8 +3(x-8)

add 8 to both sides :

y + 8 = -8 +3(x-8) + 8
y + 8 = -8 + 8 + 3(x-8)
y + 8 = 3(x-8)

Answer 7

Another way to do it:

y - y1 = m(x-x1) ... Start with the general point-slope form equation

y - (-8) = 3(x-8) ... Plug in m = 3, and (x1, y1) = (8, -8)

y + 8 = 3(x-8)

Answer 8

Ohhhhh, ok thanks . Now I understand how to write it. Thank you for helping me! (: