Question

Решите уравнение: х^2-4/х+2=0 , 4-5у/у+5-1+5у/5-у=7/у^2-25

Answer 1

1) (x² -4)/(x+2) =0
(x-2)(x+2)/(x+2) =0
x-2 =0
x =2

2) (4-5y)/(y+5) -(1+5y)/(5-y)=7/(y-5)(y+5)

((4-5y)(5-y) -(1+5y)(y+5)) /(y+5)(5-y) =7/(y-5)(y+5)
(20-29y+5y² -(5+5y²+26y)) / -(y+5)(y-5) = 7/(y -5)(y+5)
(20-29y+5y²-5-5y²-26y) / -(y-5)(y+5) =7/(y-5)(y+5)
-(15-55y)/(y-5)(y+5) = 7/(y -5)(y+5)
(-15+55y -7) /(y-5)(y+5) =0
55y -22 =0
55y =22
y =22/55
y =2/5
y =0.4