Question

x+y=4 x²+y²=45 ME AJUDEM POR FAVOR ​

Answer 1

Explicação passo-a-passo:

x+y=4

x²+y²=45

x = 4-y

x²+y²= 45

(4-y)² + y²= 45

(4-y).(4-y)+ y²= 45

16-4y-4y+y² + y²= 45

16-8y+2y²= 45

2y²-8y+16-45= 0

2y²-8y-29 = 0

a=2; b = -8; c = - 29

∆= b²-4ac

∆= (-8)²-4.2.(-29)

∆= 64+8.29

∆= 64+232

∆= 296

296:2

148: 2

74:2

37:37

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1

= 2².2.37

= √4.√2.√37

= √4.√74

= 2.√74

y = [- b +/- √∆]/2a

y = [-(-8)+/- 2√74]/2.2

y = (8 +/- 2√74)/4

y = 8/4 +/- √74/2

y = 2 +/- √74/2

y ' = 2 + √(74)/2

y " = 2 - √(74)/2

se y = (2+√(74)/2)

x '= 4-y

x ' = 4 - (2+√(74)/2)

x ' = 4 - 2 - √(74)/2

x ' = 2 - √(74)/2

Se y = 2 - √(74)/2

x " = 4 - y

x " = 4 - (2 - √(74)/2)

x" = 4 - 2 + √(74)/2

x" = 2 + √(74)/2