ABCD is a square where A is the point (0,2) and C is the point (8,4). AC and BD are diagonals of the square and they intersect at E. Find the coordinates of B and D.
I have found out the coordinate of E which is(4,3) and the equation of Bd and length of AE
slope is 1/4?
so perp slope is -4
the ans for the coordinate of B is(5,-1) & D is (3,7)
but i do not know how to derive at it
the slope form a to c aint 1 so its not a square that situated nicely like that is it?
slope from a to c is: 2/8 = 1/4
ABCD is a square in the question
e is a+c/2 for midpoint 8,4 0,2 ---- 8,6 /2 = 4,3 e is good
y=-4x+4(4)+3 y=-4x+19 is the equation of the line perp to ac and thru 4,3
hmmm, so. ; this laptop doesnt make this easier lol
we need a vector that is the length of ae
its \[\sqrt{17}\] length of ae
8,4 -4,3 ---- <4,1>; mag = sqrt(17) that ougt to be fun to play with
i cant find a way to find the coordinate through the length of ae LOL
so the vector representation of say eb is our -4/1 slope
<1,-4> is out vector ... duh lol
form e move 1,-4 and -1,4 to get to the other corners
i was tinking of finding the coordinate through the x-axis difference and y-axis difference but it doesnt seem to work
4,3 1,-4 ----- 5,-1 4,3 -1,4 ----- 3,7
i get it thx:) alot
took a bit my my brain clicked lol
So what were the correct points? For some reason, I'm getting (3,7) and (5,-1), but the question is which one is B and which one is D
Hi im very sorry could you explain what is a vector?
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a vector can be represented as a directed line segment; something like an arrow with distance and direction defines a vector
how did u arrive at a vector of (-1,4)
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the slope of a line IS its vector i took the slope of the line from A to C
not drawn correctly in this pic, but same concept nonetheless
gradient AC= 1/4 thus the vector is (-1,4 ) and gradient AB= 4 vector is (-4,1)?
the slope of the line from A to C is: C (8,4) -A (0,2) -------- 8, 2 ; slope = 2/8; 1/4 the vector from A to C is then <4 , 1>
a vector is notated the same as a point, except for the < > parts that indicate it as a vector. it is 4 wide and 1 tall; the components of its gradient (slope)
How did u get C (8,4) -A (0,2) -------- 8, 2
its called subtraction
8-0 , 4-2 these are the parts of the slope formula
its just easier for me to do them in this way then to try and sort out what goes where when its already done
but to be clear about the vector from A to C, I was a little off in my explaining. The vector from A to C is actually <8,2>; half of this is going to be to the midpoint of E, since a midpoint is in the middle <8,2> ------ = <4,1>, is our vector from A to E 2
i see thank you i will try to understand & do the question first, if I still do not understand could I still look for you? thx::)
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