SOLUTION: what is the slope-intercept of 2x-7y=-24 passing through (9,11)

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Question 453353: what is the slope-intercept of 2x-7y=-24 passing through (9,11)
Found 2 solutions by mananth, ikleyn:
Answer by mananth(16949) About Me  (Show Source):
You can put this solution on YOUR website!
2 x -7 y = -24
Find the slope of this line

-7 y = -2 x + -24 0.29
Divide by -7
y = 0.29 x + 3.43
Compare this equation with y=mx+b
slope m = 0.29 m= 0.29 ,point (9,11)
Find b by plugging the values of m & the point in
y=mx+b
11=2.57 +b
b=8.43
m=0.29
Plug value of the slope and b
The required equation is y=0.29 x+8.43

Answer by ikleyn(53614) About Me  (Show Source):
You can put this solution on YOUR website!
.
what is the slope-intercept of 2x-7y=-24 passing through (9,11)
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        In his post,  @mananth gives the answers:  the slope is  0.29,  x-intercept is  8.43.
        Both his answers are incorrect. His solution is incorrect,  too.
        I came to bring a correct solution to this problem.


We want to find the slope-intercept equation for the line parallel 2x-7y = -24 and passing through (9,11).


In standard form, this line have the same left side

    2x - 7y = c    (1)

and some constant 'c' in the right side.


To find the value of 'c', substitute the coordinates (x,y) = (9,11) into equation (1).  You will get

    c = 2*9-7*11 = -59.


So, equation (1) takes the form

    2x - 7y = -59.    (2)


To get the "slope-intercept form", express 'y' from equation (2).

It is

    y = %282%2F7%29x + 59%2F7.


Thus the slope of the sought line is  2%2F7  and its x-intercept is  59%2F7.


@mananth produced approximate decimals with only 2 correct decimals after the decimal dot - 
- but the problem asks about PRECISE values, not about their approximate values.


It is why the solution by @mananth fails and is incorrect.

Solved correctly.