Hi,
can someone please help me with this question.
1. Two sides of a rectangle have equations y=2x and 2y+x=5. Find, algebraically, the coordinates of the vertex of the rectangle formed by these sides.
DScott24
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mixed questions (need help)
Started by Dscott24, Mar 12 2006 01:13 PM
7 replies to this topic
#2
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Posted 12 March 2006 - 01:17 PM
Make a sketch of what's going on. Do you know what the question is actually asking you?
#3
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Posted 12 March 2006 - 01:21 PM
QUOTE(Steve @ Mar 12 2006, 01:17 PM) 
Make a sketch of what's going on. Do you know what the question is actually asking you?
I think i do, is it just the point where the two sides of the rectangle meet. Can you give me a hint on what im supposed to do?
DScott24
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Posted 12 March 2006 - 01:31 PM
Well, if the lines intersect then you are looking for a point which lies on both the lines, i.e. solving the equation of the lines simultaneously.
Have a look at the new Straight Lines notes for more information.
Have a look at the new Straight Lines notes for more information.
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Posted 12 March 2006 - 01:43 PM
QUOTE(Steve @ Mar 12 2006, 01:31 PM)
Well, if the lines intersect then you are looking for a point which lies on both the lines, i.e. solving the equation of the lines simultaneously.
Have a look at the new Straight Lines notes for more information.
Yeah i just tried that, although i didnt get the right answer. can you try it and tell me what u got?
DScott24
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Posted 12 March 2006 - 01:48 PM
I got (1,2).
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Posted 12 March 2006 - 01:50 PM
QUOTE(Steve @ Mar 12 2006, 01:48 PM)
I got (1,2).
Yeah thats the right answer, can you show me how you did it?
DScott24
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Posted 12 March 2006 - 01:58 PM
Ok, you have:
So all you have to do is solve them simultaneously. There are lots of ways you can do this (all covered in the notes), but I did this:
From (1),
(by multiplying through by 2), then substitute this into (2):
Then substitute this into either (1) or (2) to get the y-coordinate.
So all you have to do is solve them simultaneously. There are lots of ways you can do this (all covered in the notes), but I did this:
From (1),
(by multiplying through by 2), then substitute this into (2):Then substitute this into either (1) or (2) to get the y-coordinate.
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