Equating Ratios

lingping7

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(I'm not sure if this post is supposed to be in this topic, if it isnt , please move it.)

The question is:
If (x+y):(x-y) = 4:1, then (x^2+y^2):(x^2-y^2)= ?

The only step I could think of starting with is converting these ratios into fractions like-
(x+y)/(x-y) = 4/1

Please help me continue

Thanks in advance
 
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If (x+y) : (x-y) = 4:1, then (x^2+y^2) : (x^2-y^2)= ?

The only step I could think of starting with is converting these ratios into fractions like-
(x+y)/(x-y) = 4/1
Continue:

x + y = 4(x - y)

Then note the simplified forms of (x - y)^2, (x + y)^2, and (x - y)(x + y). ;)
 
I notice there is some similarity between the simplified forms of those things and the question, but I'm not able to substitute them in the right place.
 
I notice there is some similarity between the simplified forms of those things and the question, but I'm not able to substitute them in the right place.
What did you get for the simplified form of (x - y)(x + y)? What did you get for the simplified forms of (x + y)^2 and (x - y)^2? ;)
 
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