Error Analysis

The equation stated above is incorrect. This is also not in the slope intercept form, y=mx+b.

9= 9+10(0) 19=9+10(5) ... etc, does not equal out.

Therefore, the correct equation is y=2x+9. 9=2(0)+9 , 19=2(5)+9. The equation works out.

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In question number 22, the error is that the line should be dotted instead of a solid line because it's only "less than", NOT " less than OR EQUAL TO. "

In question number 23, the error is that the shaded area should be on the other side of the line because it is GREATER than or equal to.

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The student didn't check for the other equation, x+4y=-5.

1+4(-2)=-5. The solution does not equal -5. So it does not work.

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In question number 20, the lines should be dashed instead of solid because the equation is LESS THAN, not equal to.

In question number 21, the shaded region should be below the lines because it is LESS THAN or equal to.