Question

18) Resolva as Equações em R
a)2x+6=x+18=
b)5x–3=2x+9=
c)3(2x–3)+2(x+1)=3x+18=
d)3x–5=x–2=
x–(2x–1)=23=​

Answer 1

Resposta:

a) 2x + 6 = x + 18

2x - x = 18 - 6

x = 12

..........

b) 5x - 3 = 2 x + 9

5x - 2x = 9 + 3

3x = 12

x = 12/3 => x = 4

..........

c) 3(2x - 3 ) + 2(x + 1) = 3x +18

6x - 9 + 2x + 2 = 3x + 18

8x - 3x = 18 + 9 - 2

5x = 25 => x = 25/5 => x = 5

...........

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

2x + 3x - 15 = 4x + 9

5x - 4x = 9 + 15

x = 24

............

e) 2(x + 1) -3 (2x -5)=6x -3

2x + 2 - 6x + 15 = 6x - 3

-4x - 6x = -3 - 2 - 15

-10x = -20 (-1)

x = 20/10 => x = 2

.............

f) 3x - 5 = x - 2

3x - x = -2 + 5

2x = 3

x = 3/2

.............

g) 3x - 5 = 13

3x = 13 + 5

3x = 18 => x = 18/3 => x = 6

..............

h) x - (2x - 1) = 23

x - 2x + 1 = 23

-x = 23 - 1

-x = 22 (-1)

x = -22

............

i) 2x - ( x -1) = 5 (x - 3)

2x - x + 1 = 5x - 15

2x - x - 5x = -15 - 1

-4x = -16 (-1)

4x = 16 => x = 16/4 => x = 4