How would I work this out? Which is the equation of the given line in standard form?

–8x + 9y = 23
–8x + 9y = –23
–8x + 7y = 25
–9x + 8y = –23
http://static.k12.com/eli/ecollege/543/7_29458/2_30743_10_29468/bd160f982ed4c38b4eebe773e4b0a0e36eba41ef/media/29447d2f934e027795d77c47d6f25d0d4067ddfb/mediaasset_1331297_1.jpg

Question

How would I work this out? Which is the equation of the given line in standard form?

       –8x + 9y = 23
       –8x + 9y = –23
       –8x + 7y = 25
       –9x + 8y = –23
http://static.k12.com/eli/ecollege/543/7_29458/2_30743_10_29468/bd160f982ed4c38b4eebe773e4b0a0e36eba41ef/media/29447d2f934e027795d77c47d6f25d0d4067ddfb/mediaasset_1331297_1.jpg

compassionate · Answer

Hello, standard form is from the greatest number to the lowest. So, you will always have the form Ax + By = C.

anonymous · Answer

Thanks, but I still don't get it quite.

anonymous · Answer

Ok, so the first thing you're going to want to do is find the slope. The graph you've got gives you the two points (1/2, 3) and (-4, -1)

anonymous · Answer

And the slope of that would be the change in y over the change in x, right? So, what would that be?

anonymous · Answer

(3- -1)/(1/2- -4), which is equal to?

anonymous · Answer

That gives you the fraction 4/4.5. This can also be simplified to 8/9.

anonymous · Answer

The other thing you're going to want to figure out from the graph is the y-intercept, or where X=0. Looking at the graph, that is about 2.5

anonymous · Answer

sorry, i didn't see your replies because i stepped away for a bit. thanks for explaining, i think i've got it now :)

anonymous · Answer

Oh, swell.