Slope-intercept form is y = mx + by=mx+b.
So how do we write 8x + 9y = 18x+9y=1 in this form? Well, we need to isolate yy on one side and get everything else on the other side!
1. Our first step is to subtract 8x8x from both sides, so that only 9y9y remains on the left side.
8x + 9y = 18x+9y=1
cancel(8x) + 9y cancel(color(red)(- 8x)) = 1 color(red)(- 8x)
9y = 1 - 8x
We can switch the order of the 1 and the -8x, because of the commutative property. So now we have
9y = -8x + 1
2. Divide both sides by 9 to get only y on the left side.
(9y)/9 = (-8x)/9 + 1/9
y = -8/9x + 1/9
Now the equation is in slope-intercept form!
The slope (m) is -8/9 and the y-intercept (b) is 1/9.
