What is the x-coordinate of the x-intercept of the line that passes through points (-5, 3) and (1, -3)?

Question

anonymous · Answer

are u looking for the slope? or the y-mx+b?

anonymous · Answer

The x coordinate.

anonymous · Answer

what the answer they give u on it

anonymous · Answer

They didnt give me any

anonymous · Answer

oh ok will I got slope is -1

anonymous · Answer

I dont get it. So whats the x coordinate??

anonymous · Answer

@jim_thompson5910 can you help??

jim_thompson5910 · Answer

first you need to find the equation of the line through the two points

jim_thompson5910 · Answer

are you able to do that?

anonymous · Answer

nope. can you bring me through the process?

jim_thompson5910 · Answer

do you know how to find the slope of the line through those two points?

anonymous · Answer

no

jim_thompson5910 · Answer

have you seen the slope formula  m = (y2-y1)/(x2-x1) before?

anonymous · Answer

ohhh yes I have. Ill try to solve for it just a sec

jim_thompson5910 · Answer

ok plug in the given points and tell me what slope you get

anonymous · Answer

6/6 = 1

anonymous · Answer

so @jim_thompson5910  the slope is one tho

jim_thompson5910 · Answer

not quite


m = (y2-y1)/(x2-x1)


m = ( -3- 3)/(1-(-5))


m = ( -3- 3)/(1+5)


m = (-6)/6


m = -1

jim_thompson5910 · Answer

You lost a sign somewhere

anonymous · Answer

oh yup I did :/ so now whats next??

jim_thompson5910 · Answer

now use this to find the y-intercept

jim_thompson5910 · Answer

y = mx+b

y = -1*x + b

3 = -1*(-5) + b

3 = 5 + b

b = ??

anonymous · Answer

b=-2

jim_thompson5910 · Answer

so the equation is y = -x - 2

jim_thompson5910 · Answer

to find the x-intercept, you plug in y = 0 and solve for x

anonymous · Answer

x=-2

jim_thompson5910 · Answer

good

anonymous · Answer

yayyy:)) thank you can you help me with one more? 
Mary is 14 years younger than her sister Jane. In four years, Jane will be 3 times older than Mary. How old is Jane now?

3

7

17

21

jim_thompson5910 · Answer

how far did you get here

anonymous · Answer

m+14=j

jim_thompson5910 · Answer

Mary is 14 years younger than her sister Jane

means that

M = J + 14

anonymous · Answer

that wouldnt really be possible cause jane is older than mary

jim_thompson5910 · Answer

oh wait, misread that, it should be M = J - 14

sorry about that

jim_thompson5910 · Answer

so if you rearrange terms you get J = M + 14

jim_thompson5910 · Answer

in 4 years, Jane is J+4 years old

in 4 years, Mary is M+4 years old

anonymous · Answer

m=j-14
 j+4=3(m+4)
solving we get mary =3 jane=17

jim_thompson5910 · Answer

good, you got it