A distancia entre os pontos A(-2,y) e b((6,7) é 10. O valor de y é?
a) -1
b) 0
c) 1 ou 13
d) -1 ou 10
e) 2 ou 12
Obrigada...=)
√(-2-6)²+(y-7)²=10²
64+y²-14y+49=100
y²-14y+13=0
∆=196-52=144
y=(14±√144)/2
y=(14±12)/2
y==26/2=16
y"=2/2=1
letra C
(10)²=(7-y)²+(6+2)²
100=49-14y+y²+64
y=14+-raiz 196-52/2
y=14+-12/2
y1=14+12/2=13
y"=14-12/2=1
y=1 ou 13 letra (C)
Copyright © 2024 QUIZLIB.COM - All rights reserved.
Answers & Comments
√(-2-6)²+(y-7)²=10²
64+y²-14y+49=100
y²-14y+13=0
∆=196-52=144
y=(14±√144)/2
y=(14±12)/2
y==26/2=16
y"=2/2=1
letra C
(10)²=(7-y)²+(6+2)²
100=49-14y+y²+64
y²-14y+13=0
y=14+-raiz 196-52/2
y=14+-12/2
y1=14+12/2=13
y"=14-12/2=1
y=1 ou 13 letra (C)