If a student writes (9, 4) as (4, 9), what is the main mistake?
Answer and explanation
Correct answer: Writing coordinates in reverse order
The governing convention for an ordered pair is (x, y): the first coordinate gives horizontal displacement and the second gives vertical displacement. Thus (9, 4) means x = 9 and y = 4, whereas (4, 9) means a completely different point with x = 4 and y = 9. Writing one in place of the other reverses the coordinate order, so option B is correct. The error is not about naming axes, because the coordinates themselves have been interchanged. It is not about failing to draw a line, and option D describes a correct action rather than a mistake. Careful use of (x, y) prevents this error.
Frequently asked questions
What is the correct answer to this question?
Writing coordinates in reverse order
Why is this the correct answer?
The governing convention for an ordered pair is (x, y): the first coordinate gives horizontal displacement and the second gives vertical displacement. Thus (9, 4) means x = 9 and y = 4, whereas (4, 9) means a completely different point with x = 4 and y = 9. Writing one in place of the other reverses the coordinate order, so option B is correct. The error is not about naming axes, because the coordinates themselves have been interchanged. It is not about failing to draw a line, and option D describes a correct action rather than a mistake. Careful use of (x, y) prevents this error.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Pair of Linear Equations in Two Variables. Topic: Graphical method of finding solutions..
