How do you find the intercepts for #3x + 9y = 18?

1 Answer
Jul 3, 2015

To find the x-intercept, substitute 0 for y, then solve for x.
To find the y-intercept, substitute 0 for x, then solve for y.

Explanation:

#3x+9y=18#

X-Intercept

Substitute #0# for #y#.

#3x+9(0)=18#

#3x=18#

Divide both sides by #3#.

#x=6#

Y-Intercept

Substitute #0# for #x#.

#3(0)+9y=18#

#9y=18#

Divide both sides by #9#.

#y=2#

graph{3x+9y=18 [-10, 10, -5, 5]}