Find two positive numbers whose difference is 8 and the sum of whose squares is 914. Give the answers in ascending order
i just need the equations
would it be x-y=8 for the first one?
Yes, and x^2+y^2=914 for the second.
thank you, i tried that before, but i didn't get the right answer
can i add y^2 + y^2, and it'll be y^4?
i'm getting y^2 +y^2=914-64
but then i'm not sure what to do after; do i add the y's or do i take the square of 850?
If you do y^2+y^2, it will be 2y^2 Then 2y^2=850, then divide by 2--- y^2=425 But that is not a perfect square. Hole on. Let me try something.
ok
x-y=8 ----> -y=8-x---->y=-8+x k=x^2+y^2 k=x^2+(-8+x)^2 k=x^2+64-16x+x^2 k=2x^2-16x+64 Next we factor. Before I continue, did you understand that part?
yes
so it'll be 2(x -8)(x-8)
and then x-8=0 x=8 and same thing for the other x?
Yes, that will be right, but now, I'm trying to figure how we will find what y is.
ok
Yay I got the answer. So I did something wrong. Instead of k=2x^2-16x+64 it should have been 914=2x^2-16x+64 Then subtract 914 from both sides. 0=2x^2-16x-850 Then divide the right side by 2 0=x^2-8x-425 Factor 0=(x-25)(x+17) Then solve x=25 and x=17 25-17=9 625+289=914 So the numbers are 25 and 17. That took awhile lol
LOL yes that's right! Thank you so much!
Np. It would've bugged me all day if I didn't figure it out. :)
i'm sure it would have! lol
are you also good at logs?
Yes. Do you have a log question?
yes i do, i'll post it now :)
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