Question

1) Resolva as equações do 1o grau abaixo, utilizando o método prático:

a) 4x + 18 = 2x + 28 f) 7x – 3x = 70 – 30

b) 25x = 50 g) 9y – 25 + y = 32 + 3y – 1

c) 50x = 25 h) 29 + 13b + 5b = 11

d) 3x = 40 + 2x – 7 + 5x – 22 i) x + x + x + 30 = 2x + 3x + 4x

e) 23 – 8y – 15 = – 2y + 26 j) 7a + 35 – 2a – 19 = 5a + 26 – 4a + 20 – 6a

f) 7x – 3x = 70 – 30

g) 9y – 25 + y = 32 + 3y – 1

h) 29 + 13b + 5b = 11

i) x + x + x + 30 = 2x + 3x + 4x

j) 7a + 35 – 2a – 19 = 5a + 26 – 4a + 20 – 6a

Answer 1

Resposta: a) x=5 b) x=2 c) x=0,5 ou 1/5 d) x=-11/4 e)y=9/5 f)x=10 g) y=8 h) b=-1 i) x=5 j) a=5

Explicação passo a passo:

a) 4x-2x=28-18

2x=10

x=10/2

x=5

b) x=50/25

x=2

c) x=25/50

x=0,5 ou x=1/5

d) 3x=11+2x+5x

3x=11+7x

3x=7x+11

3x-7x=7x+11-7x

4x=11

4x/4=11/4

x=-11/4

e) -8y-2y=+26-23+15

-10y=+18

y=+18/10

y=9/5

f) 4x=70-30

4x=40

4x/4=40/4

x=10

g) 10y-25=32+3y-1

10y-25=31+3y

10y-25=3y+31

10y-25+25=3y+31+25

10y=3y+56

7y=56

7y/7=56/7

y=8

h)29+18b=11

18b+29=11

18b+29-29=11-29

18b=-18

18b/18=-18/18

b=-1

i)3x+30=2x+3x+4x

3x+30-30=9x-30

3x+30=9x

3x=9x-30

-6x=-30

-6x/6=-30/6

x=5

j) 7a+16-2a=5a+26-4a+20-6a

5a+16=5a+26-4a+20-6a

5a+16=5a+46-4a-6a

5a+16=5a+46

5a+16-16=5a+46-16

5a=-5a+30

5a+5a=-5a+30+5a

10a=30

10a/10=30/10

x=3

Espero ter ajudado :)