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#1 2014-08-25 15:42:37
- math4matthew
- Member
- Registered: 2014-08-25
- Posts: 3
Practice SAT problem
If x and y are positive consecutive odd integers, where y>x, which of the following is equal to y^2-x^2?
a) 2x
b) 4x
c) 2x+2
d) 2x+4
e) 4x+4
oops..
got it...
just plug x=1, y=3
then only answer is e
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#2 2014-08-26 02:59:11
- ShivamS
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- Registered: 2011-02-07
- Posts: 3,648
Re: Practice SAT problem
Any pair of consecutive odd integers differ by 2. So if y>x, then y = x + 2.
y² - x² = (x+2)² - x²
= 4x + 4.
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