SOLUTION: Please help! {{{ What are the coordinates of the y-intercept of the graph y=8x-2? }}}

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Question 487247: Please help! +What+are+the+coordinates+of+the+y-intercept+of+the+graph+y=8x-2%3F+
Found 3 solutions by jim_thompson5910, MathLover1, Theo:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Any equation in the form y=mx%2Bb+ has a slope of m and a y-intercept of b.


In this case, m=8 and b=-2

So the y-intercept is -2, which is the point (0,-2)

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

What are the coordinates of the y-intercept of the graph y=8x-2
y=8x-2...this is equation in slope-intercept form y=mx%2B-b where m is a slope and b is y-intercept
as you can see b=-2; the coordinates of the y-intercept are (0,-2)
let's see it on a graph:
+graph%28+500%2C+500%2C+-5%2C+5%2C+-5%2C+5%2C+8x-2%29+

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
equation is y = 8x - 2

standard form of a linear equation is ax + by = c
slope intercept form of a linear equation is y = mx + b
point slope form of a linear equation is y - y1 = m(x - x1)

m is the slope
b is the y intercept

your equation is y = 8x -2

this is in the slope intercept form of a linear equation of y = mx + b

m = 8
b = -2

the slope of your equation is 8
the y intercept of your equation is -2

the graph of your equation looks like this:
graph%28400%2C400%2C-2%2C2%2C-30%2C20%2C8x-2%2C-2%29

i drew a horizontal line at y = -2 so you can see that the equation crosses the y-axis at y = -2.

if you plot the values of y from the values of x from x = -3 to x = +3, you would get a table that looks like this: 

           x        y = 8x-2     change in x    change in y
          -3       -26                 -              -
          -2       -18                 1              8
          -1       -10                 1              8
           0       -2                  1              8
           1        6                  1              8
           2        14                 1              8
           3        22                 1              8


the table shows that when x = 0, y = -2.
this means the y intercept is equal to -2.

the change in x column is the difference between the value of x in each row and the value of x in the row above it.

the change in y column is the difference between the value of y in each row and the value of y in the row above it.

you can see that when x change by a value of 1, the corresponding value of y changes by a value of 8.

that's your slope of 8 which is equal to the change in y divided by the change in x.