How can I solve the following problem? ]http://i.imgur.com/nugOvXJ.png (i.imgur)
The solution says the triangles have same height and hence the lengths are proportional.
@WhiteFlameAB Draw the altitude from A to BC. That is the “height” they were referring to.
@MITer94 Thanks! I have another one here : http://i.gyazo.com/34b568219a25f44531483a0cc6629082.png
@WhiteFlameAB
try to figure out the numbers for eg.if you take in a as 10 and b as 9 you get 19 try 5 & 4 you will get 9
Try out 4 and 3 you will get 7.
So 4*3 gives you 12.
D is the answer
@WhiteFlameAB A solution that I prefer is to use difference of squares, I.e. (a-b)(a+b) = 7. 7 is prime, and since a+b is positive, a-b is also positive so a+b = 7 and a-b = 1. Solve to get a=4, b=3.
@UAS998 I’ve got it using substitution, but I was wondering if there was an algebraic solutiion…
For all numbers a and b, let a#b = a^2 - 3ab^2. What is the value of |5#(2#1)| ?
@MITer94 Thanks! And it can be the other way also right?(where a - b = 7 and a + b = 1)
@UAS998 It is -35.
I have a few more questions guys:
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Official SAT : http://i.gyazo.com/07c39121d54d32b0ceeca9eb638b90a1.png
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Is the degree measure always measured with respect to the center of the circle ?
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( http://i.gyazo.com/f919ed053d957d0e8d7287f3862eace3.png ) I’ve found the answer by taking the mid-point, but I do not understand how do we know that the max y value is at the midpoint.
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( http://i.gyazo.com/190655a93f6842e7291e28e2524e9f5b.png ) After multiplying 45 = 20, we get only one order of the list : (4,5),(4,6),(4,7)… But we do not obtain the reverse, such as : (5,4),(5,6),(5,8) and so on. Hence, shouldn’t it be (202) - 2? ( -2 since 6,6 and 8,8 are repeating)
@WhiteFlameAB can you show me the method?
@WhiteFlameAB
For 1st question
https://www.youtube.com/watch?t=286&v=BSgyZNEO-QY
@UAS998 Which method are you talking about?
Does anyone of a way to temporarily define a function (accepts x value and gives y) on a TI-84 ?. It will come handy in “symbol” questions like @UA998’s.
EDIT: I finally understood what “method” you were asking 
My solution : http://i.gyazo.com/8421a1f99ca50cf8663a1cda3c173000.png
And the solution is +35, not -35. I missed the modulus symbol.
@WhiteFlameAB For 3rd question I think since nothing is mentioned so it’s just an assumption.
According to the figure it looks like the mid point,between the value gives the highest value of y.
@UAS998 Yes, that’s what is bothering me; how can we just assume a point like that?..Also, check my edit.
@WhiteFlameAB Thanks a lot. :)>-
UPDATE:
1)Is the degree measure always measured with respect to the center of the circle ?
2)( http://i.gyazo.com/f919ed053d957d0e8d7287f3862eace3.png ) I’ve found the answer by taking the mid-point, but I do not understand how do we know that the max y value is at the midpoint.
3)( http://i.gyazo.com/190655a93f6842e7291e28e2524e9f5b.png ) After multiplying 45 = 20, we get only one order of the list : (4,5),(4,6),(4,7)… But we do not obtain the reverse, such as : (5,4),(5,6),(5,8) and so on. Hence, shouldn’t it be (202) - 2? ( -2 since 6,6 and 8,8 are repeating)
4)Does anyone of a way to temporarily define a function (accepts x value and gives y) on a TI-84 ?. It will come handy in “symbol” questions like @UA998’s.
5)( http://i.gyazo.com/67832baec60c211503f2efc4751b64c3.png ) I have solved the question this way: ( http://i.gyazo.com/54bc685b7c57a9d26ed3dca79e8486f6.png ) but the answer seems to be 1. What am I doing wrong?
@WhiteFlameAB
1/m is inversely proportional to n^2.
You took it as directly proportional.
1/m=(k*1)/n^2
n^2/m=k
2^2/2=2
1/m=(2*1)/(sqrt of 2)^2
1/m=2/2
1/m=1
m=1/1
m=1
Oh OK, Thanks! Are you also taking SAT tomorrow?
Yes.
@WhiteFlameAB (1) It is a theorem that the measure of a central angle of a circle is equal to the measure of the arc it intercepts (central angle has vertex at the center of the circle).
(2) The vertex of a parabola is always midway between the two x-intercepts (whenever there are two x-intercepts).
(3) The question says ordered pairs of the form (x,y) - it does not say that pairs of the form (y,x) are allowed.
(4) Press the Y= button and enter your function under Y1. You can then use this function anytime by pressing VARS, scrolling to Y-Vars, selecting Function, and then Y1. For example, typing Y1(2) will evaluate the function at x=2.