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Annabelle wanted to find the y value for when x is 0 (y intercept). Here are her steps. Did Annabelle make a mistake? If so, which one? If not, indicate that as well

Annabelle wanted to find the y value for when x is 0 (y intercept). Here are her steps-example-1
User Subin Babu
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2 Answers

4 votes

Answer:

Explanation:

Annabelle did not make a mistake. you have to substitute 0 in for x then dived the equation by 2 giving you the answer of 4. She is correct. A rockstar as the answer says. :) hope this helped!

User Atalayasa
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6 votes

Answer: She made no mistakes

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Reason:

She wants to find the y value when x = 0. This is why she replaced every copy of x with 0. Step 1 is correct.

Step 2 is also correct because 3 times 0 is 0. She multiplied correctly.

Step 3 is correct because she needs to undo the "2 times" that is applied to y, in order to isolate it. Division is the inverse operation of multiplication.

Step 4 is correct because 8/2 is 4

Every step she did is correct, and so is the final answer.

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Here's one way Annabelle could check her work

3x+2y = 8

3*0+2*4 = 8 .... plug in x = 0 and y = 4

0 + 8 = 8

8 = 8

We get the same thing on both sides, which confirms that x = 0 pairs up with y = 4. In other words, (x,y) = (0,4) is a solution to 3x+2y = 8.

The point (0,4) is on the line 3x+2y = 8. This point is the y intercept where the graph crosses the y axis.

User AntR
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