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

Answer 1

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.

#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]}

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Answer 2

Genesis Allen

To find the intercepts for the equation 3x + 9y = 18, you can set one variable to zero and solve for the other variable.

To find the x-intercept, set y to zero: 3x + 9(0) = 18 3x = 18 x = 6

To find the y-intercept, set x to zero: 3(0) + 9y = 18 9y = 18 y = 2

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.