Question

nas proporsoes a  seguir , calcule o valor do x :

a)7/5=x/10                            
b)5x/2=1/6  
 c)6/x=12/5                         
d)2/3x=5/30
e)x+7/8=5/4
f)x-2/5=2+x/7

   

Answer 1

a)7/5=x/10 : 5x=70 : x=70/5 : x=14
b)5x/2=1/6 : 30x=2 : x=2/30 : x=1/15
c)6/x=12/5 : 12x=30 : x=30/12 : x=5/2
d)2/3x=5/30 : 15x=60 : x=60/15 : x=4
e)x+7/8=5/4 : 4x+28=40 : 4x=40-28 : x=12/4 : x=3
f)x-2/5=2+x/7 : 10+5x=7x-14 : 12x= -24 : x= -24/12 : x= -2

Answer 2

a) 7/5 = x/10
5x = 7*10
5x = 70
x = 70/5
x = 14

b) 5x/2 = 1/6
5x*6 = 2*1
30x = 2 .(simplifique por 2)
15x = 1
x = 2/15

c) 6/x = 12/5
12x = 6*5
12x = 30
x = 30/12 (simplifique por 6)
x = 5/2

d) 2/3x = 5/30
3x*5 = 2*30
15x = 60
x = 60/15
x = 4

e) x + 7/ 8 = 5/4
8*5 = 4.(x + 7)
40 = 4x + 28
4x = 40 - 28
4x = 12
x = 12/4
x = 3

f) x - 2/ 5 = 2 + x/ 7
5.(2 + x) = 7.(x - 2)
10 + 5x = 7x - 14
7x - 5x = 14 + 10
2x = 24
x = 24/2
x = 12