ab=3 means b=3/a
ac=5 means c = 5/a
so bc=4 means (3/a)(5/a) = 4 or a = 15/4
b = 3/a = 3*(4/15) = 12/15 = 4/5
c = 5/a = 5*(4/15) = 4/3.
This is one combination, look for others.
Help with a math problem plz. Problem: ab=3, bc=4, ac=5, find all possible (a,b, c). plz show work. thx?
sorry...can't remember my algebra
Reply:ab = 3 so a = 3/b
bc = 4 so c = 4/b
ac = 5 so c = 5/a
c = c so 4/b = 5/a or a/5 = b/4 or a = 5b/4 = 3/b
so that b^2 = 12/5, b = 2sqr[3/5]
a = 3/b = 3/(2sqr[3/5])
c = 4/b = 4/(2sqr[3/5])
Reply:ab=3, bc=4, ac=5
transpose equation 1
b=3/a
sub into equation 2
(3/a)(c)=4
transpose equation 3
a=5/c
sub into derived equation
3/(5/c)*c=4
3c/5*c=4
3c^2/5=4
3c^2=20
c^2=20/3
c=2.58
since bc=4
b=4/2.58
=1.55
since ac=5
a=5/2.58
=1.94
so a=1.94, b=1.55, c=2.58
for another solution, take the negative squre root value of c, instead of the positive, and sub into formulas again.
Reply:Multiplying all three together, you have:
(abc)^2 = 60
taking the square root gives:
abc = 2 sqrt(15) or -2 sqrt(15).
So c = abc / ab = 2 sqrt(15) / 3 or - 2sqrt(15) / 3
b = abc / ac = +- 2 sqrt(15) / 5
a = abc / bc = +- sqrt(15) / 2
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