Question

a)15+3x+2x-4x+20x=39+1

b)20x=40-13x+2x

c)7.(y+7)=49

d)z+2z+4.(z-2)=40

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Answer 1

Resposta:

a)

$15+3x+2x-4x+20x=39+1 \\ 3x + 2x - 4x + 20x = 40 - 15 \\ 21x = 25 \\ x = \frac{25}{21}$

b)

$20x=40-13x+2x \\ 20x + 13x - 2x = 40 \\ 31x = 40 \\ x = \frac{40}{31}$

c)

$7.(y+7)=49 \\ 7y + 49 = 49 \\ 7y = 49 - 49 \\ 7y = 0 \\ y = \frac{0}{7} \\ y = 0$

d)

$z+2z+4.(z-2)=40 \\ z + 2z + 4z - 8 = 40 \\ z + 2z + 4z = 40 + 8 \\ 7z = 48 \\ z = \frac{48}{7}$

Answer 2

a) 15 + 3x + 2x - 4x + 20x = 39 + 1

15 + 21x = 40

21x = 40 - 15

21x = 25

x = 25/21

b) 20x = 40 - 13x + 2x

20x = 40 - 11x

20x + 11x = 40

31x = 40

x = 40/31

c) 7(y+7) = 49

y + 7 = 7

y = 0

d) z + 2z + 4(z-2) = 40

z + 2z + 4z - 8 = 40

7z - 8 = 40

7z = 40 + 8

7z = 48

z = 48/7