Nice Algebra Math Simplification Find the Value of a and b

[@don3com]

3:38 - 3:48 how do you go from
a + 25/a = 15
to
(a² + 25)/a = 15 ?

[@CharlesChen-el4ot]

a +b + (ab)^1/2 =25
a+b = 25-5 =20
ab = 25
(20-b)*b = 25
b^2-20b +25 =0
b =1/2(20+/- (400- 100)^1/2)
b = 10 +/- 5*3^1/2

[@takashikudo324]

ルートa、ｂはt^２－５＊t－１５＝０の根だから、この方程式を解いて二乗すれば、すぐ出てくる。