3) ) Resolva as seguintes equações
a) 7(x - 5) = 3 (x + 1)
b) 3 ( x - 2 ) = 4 (-x + 3)
c) 2 (x +1) - (x -1) = 0
d) 5(x + 1) -3 (x +2) = 0
e) 13 + 4(2x -1) = 5 (x +2)
f) 4(x + 5) + 3 (x +5)= 21
g) 2 (x +5 ) - 3 (5 - x) =10
h) 8 ( x -1) = 8 -4(2x - 3)
Respostas
Explicação passo-a-passo:
a) 7(x - 5) = 3 (x + 1)
7x-35=3x+3
7x-3x=3+35
2x=358
x=38/2
x=19
b) 3 ( x - 2 ) = 4 (-x + 3)
3x-6= -4x+12
3x+4x=12+6
7x=18
x=18/7
c) 2 (x +1) - (x -1) = 0
2x+2-x+1=0
2x-x+2+1=0
x+3=0
d) 5(x + 1) -3 (x +2) = 0
5x+5-3x-6=0
5x-3x+5-6=0
2x-1=0
e) 13 + 4(2x -1) = 5 (x +2)
13+8x-4=5x+10
8x-5x=10-13+4
3x=10+4-13
3x=14-13
3x=1
x=1/3
f) 4(x + 5) + 3 (x +5)= 21
4x+20+3x+15=21
4x+3x=21-20-15
7x=21-35
7x=14
x=14/7
x=2
g) 2 (x +5 ) - 3 (5 - x) =10
2x+10-15+3x=10
2x+3x=10-10+15
5x=15
x=15/5
x=3
h) 8 ( x -1) = 8 -4(2x - 3)
8x-8=8-8x+12
8x+8x=8+12+8
16x=28
x=28/16
x=7/4
Resposta:
a)
7(x-5)=3(x+1)
7x-35 = 3x+3
7x-3x=3+35
4x=38 x=9,5
b)
3x-3 = -4x+12
3x+4x = 12+3
7x=15 x=15/7 x= 2,14
c) NÃO LEMBRO
d) 5x+5 -3x-6 = 0
2x= 0 +6 -5
2x = 1
x=1/2 x= 0,5
e) 13+ 8x- 4 = 5x+10
8x-5x = 10 +9
3x = 19 x=19/3 x=6,33
f) 4x+20 +3x +15 = 21
7x = 21 -35 =
7x = -14 .(-1)
x = 14/7 x= 2
g) 2x + 10 - 15 +3x = 10
5x = 10 + 15 -10
5x = 15 x=15/5 x= 3
h) 8x-8 = 8-8x + 12
8x+8x = 20 + 8
16x = 28 x=28/16 x= 1,75
Explicação passo-a-passo: