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How do you find the x and y intercepts for # y = 3x - 7#?

Answer 1

Savannah Anderson

The x-intercept is #(-7/3,0)#.

The y-intercept is #(0,-7)#.

#y=3x-7#

The x-intercept is the value for #x# when #y=0#.

Substitute #0# for #y#.

#0=3x-7#

Subtract #3x# from both sides.

#-3x=-7#

Divide both sides by #-3#.

#x=-7/3#

The y-intercept is the value of #y# when #x=0#.

Substitute #0# for #x#.

#y=3(0)-7#

#y=-7#

The x-intercept is #(-7/3,0)#. The y-intercept is #(0,-7)#

graph{y=3x-7 [-11.05, 10.715, -8.21, 2.675]}

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Answer 2

Isaiah Anthony

To find the x-intercept, set y = 0 and solve for x. To find the y-intercept, set x = 0 and solve for y.

For x-intercept: 0 = 3x - 7 3x = 7 x = 7/3

For y-intercept: y = 3(0) - 7 y = -7

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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.