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Use the intercepts to graph the equation.
7x - 3y = 21

User Tary
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2 Answers

4 votes

Answer:

x-intercept (3,0)

y-intercept (0,-7)

Explanation:

The x-intercept is when y is 0.

We are going to replace y with 0 giving us:

7x-3(0)=21

7x =21

Divide both sides by 7:

x =21/7=3

So the x-intercept is (3,0). So go on the x-axis and count 3 to the right of the origin. Put a dot there.

The y-intercept is when x is 0.

We are going to replace x with 0 giving us:

7(0)-3y=21

-3y=21

Divide both sides by -3:

y=21/-3=-7

So the y-intercept is (0,-7). So go on the y-axis and count down 7 units from the origin. Put a dot there.

Connect your dots with a straightedge and you are done. Extend it pass the points and both directions.

You may see the attachment for my graph of this equation using the intercepts to guide me in the graphing of the line.

Use the intercepts to graph the equation. 7x - 3y = 21-example-1
User Danny Guo
by
5.0k points
3 votes
Substitute 0 into X or Y first , then solve for the variable you isolated . 7(0) - 3y = 21 and then 7x - 3(0) = 21
User Kavare
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5.2k points