Question

resolva os sistemas de equacoes 12x+12y=7xy xy=12

Answer 1

12x+12y=7xy
x.y=12
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12x+12y=7xy
x=12-y
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12x+12y=7xy
12(12-y)+12y=7(12-y)y
144-12y+12y=(84-7y)y
144=84y-7y^2
-7y^2+84y-144=0
a=-7...b=84...c=-144

Vamos usar a formula DELTA
delta = b^2 4 a c
delta = (84)^2 - 4 (-7)(-144)
delta = 7.056 + 21(-144)
delta = 7.056 - 3.024
delta = 4.032

Vamos usar a formula de BASKARA
y = -b+,-\/delta / 2a
y =-(84)+,-\/4.032 /2(-7)
y = -84+,- 63,49 / -14
y1 = -84+63,49/-14》y1 = - 20,51/-14》y1=5,,13
y2 = -84-63,49/-14》y2 =-147,49/-14》
y2= 10,54


x1=12-y1
x1=12-5,13
x1=6,87

x2=12-y2
x2=12-10,54
x2=1,46