Respostas

2014-06-06T23:16:33-03:00
D=√(x2-x1)²+(y2-y1)²
√5= √(0+1)²+(y-5)²
(√5)²= (√(0+1)²+(y-5)²) ²    elevando ambos lados 

5= 1+(y-5)²
5=1+y²-10y+25
1+y²-10y+25=5
y²-10y+21=0

Δ = b² - 4.a.c 
Δ = -102 - 4 . 1 . 21 
Δ = 100 - 4. 1 . 21 
Δ = 16

y = (-b +- √Δ)/2a
y' = (-(-10) + √16)/2.1            y'' = (-(-10) - √16)/2.1
y' = 14 / 2                           y'' = 6 / 2
y' = 7                                  y'' = 3
7 4 7