In square ABCD, AD is 4 centimeters, and M is the midpoint of CD. Let O be the intersection of BM and diagonal AC. What is the ratio of OC to OA? If your answer is b a , then find a + b .
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D N to midpoint of A B .
Draw a lineThe lines M B and D N divide the diagonal into three equal segments because C M = M D implies C O = O P and B N = N A implies O P = P A .
So O A O C = 2 1 .
By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
I did it by making lines of the form y = m x + b for A C and B M , and using D, or the bottom left corner of the square, as the origin on a coordinate plane. Then I found the intersection O of the two lines to be ( 3 8 , 3 4 ) . Then I simply found the distance from O to the x-intercept of A C , the length of line O C , which was 3 4 2 . Then I found the distance from O to the y-intercept of A C , the length of O A , which was 3 8 2 . Dividing them I got 2 1 , so the answer was 1 + 2 = 3 .
Eh, coordinate geometry is pretty messy. You can just logic your way through it. But still, great job!
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By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
it's pretty complex
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By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
This is what I exactly do before i know about similarity. But great job!
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By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
Solution:
find the equations of the line
a. line AC is an identity with negative y so, x = -y
using (y-y1) = (y2-y1)(x-x1)/(x2-x1)
b. line BM is y = 2x - 8
Find the intersection
a. y= -x ; -x = 2x - 8; so x = 8/3 and y = -8/3
3.AC=sqrt((2(4^2 )))=4√2 ; AO= sqrt((2(8/3)^2 ))=8/3 √2
AC - AO = OC = 4√2- 8/3 √2 = 4/3 √2
a = AC ; b =AO ; a/b=1/2 ; a+b=3
By using pythagoras theorem i find the hypotenuse AC=4√2 now, AC= 3 × O C . so, OC= 3 4 √ 2 and OA= 2 × O C . so, OA= 3 8 √ 2 According to the question OC:OA= 3 4 √ 2 : 3 8 √ 2 =1:2 so, the answer is 3. Sorry I can't draw the picture.
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triangle OMC is similar to triangle OAB. and MC:AB=1:2. Therefore, OC:OA=1:2.