Question

1)determine a solução das equações do 1° grau com uma icógnita sendo U=IR

a)25x-17=10x+28

b)7x+40=11x+60-2x

c)5(x-2)-7(x+1)=9.(3-2x)

d) 6(x-3)-4(x+2)=9x-(5x+3)

Answer 1

a) 25x-17=10x+28
25x-10x=28+17
15x=45
x=45/15= 3

b)7x+40=11x+60-2x
7x+2x-11x=60-40
-2x=20
x=20/-2= -10 ou 10

c)5(x-2)-7(x+1)=9(3-2x)
5x-10-7x-7=27-18x
5x-7x+18x=10+7+27
16x=34
x=34/16

d)6(x-3)-4(x+2)=9x-(5x+3)
6x-18-4x-8=9x-5x-3
6x-4x-9x+5x=18+8-3
-2x=23
x=23/-2

Answer 2

a)25x-17=10x+28 ==> 25x-10x = 28+17 ==> 15x=45 ==> x = 3
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b)7x+40=11x+60-2x ==> 9x-7x = 40-60 ==> 2x = - 20 ==> x = - 10
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c)5(x-2)-7(x+1)=9.(3-2x) ==> 10x-10-7x-7=27-18x ==> 3x+18x=27+17

21x = 44 ==> x = 44/21
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d) 6(x-3)-4(x+2)=9x-(5x+3) ==> 6x-18-4x-8 = 9x-5x-3 ==>4x-2x= - 23

2x = - 23 ==> x = - 23/2