find three consecutive positive integers such that the sum of the squares of the first and second equals the square of the third
Without doing the algebra, you could consider the smallest Pythagorean triple.
let the smallest number be x so,other 2 numbers are x+1,x+2 so \(x^2+(x+1)^2=(x+2)^2\) solve for x.
how?
use \( (a+b)^2=a^2+2ab+b^2 \)
u will get a quadratic in x.
im sorry but can you help me step by step?
\(x^2+(x+1)^2=(x+2)^2-->x^2+x^2+2x+1=x^2+4x+4\) ok?
which gives \(x^2-2x-3=0\) which when u solve gives,x=-1,3 but as x is positive,x=3 only. so the numbers are 3,4,5.
So next step is \[2x ^{2} +2x+1=x^{2}+4x+2\]
u can subtract x^2+4x+4 from both sides.
but how do i go from x^2-2x-3=0 to x=3?
thats quadratic equation! u know any method to solve quadratic equations??
no...
x^2+(x+1)^2=(x+2)^2 Use wolfram or something to solve for it lol.
ok, x^2-2x-3=0 so, \(x^2-3x+x-3=0\) \(x(x-3)+1(x-3)=0\) \((x+1)(x-3)=0\) ok ? which step u did not understand?
am9998, if you do not know how to solve quadratic equations, why are you working on this problem? Are you expected to use guess-and-check methods?
No we were expected to know this. but my I didnt learn this.
so far i understand but whats the next step?
\((x+1)(x-3)=0\) so, x+1=0 OR x-3=0 so, x=-1 OR x=3 but x is positive so x=3 only.
got it?
yes thanks
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