How do you find the slope and intercept of 8x -y=9?

May 3, 2018

Slope of the line = $8$

x-intercept = $- \frac{9}{8}$

y-intercept = $- 9$

Explanation:

From linear equation of a line, $y = m x + c$ or $y = m x + b$
Slope of a line is m and y-intercept is c (or b).
So first we have to make y the subject in $8 x - y = 9$
$8 x - y = 9$
$- y = 9 - 8 x$
Multiply by -1 both sides, we get:
$\left(- 1\right) . - y = \left(- 1\right) .9 - \left(- 1\right) \left(8 x\right)$
$y = - 9 + 8 x$
$y = 8 x - 9$ ------> this is now same as $y = m x + c$

Hence slope is $8$ and y-intercept is $- 9$.

for x-intercept, put $y = 0$ and we get:
$0 = 8 x - 9$
$9 = 8 x$
$x = \frac{9}{8}$
Hence, x-intercept is $\frac{9}{8}$