Question

1.Rezolvati urmatoarele ecuatii,unde x este numar natural:
39=5x - 1
73=10x + 23
90 = 14 x - 8
2.Rezolvati urmatoarele ecuatii , unde ex este numar natural:

3(x-1) = 15
b)5(x + 2 ) = 20
c)4(x-7)=28
d)6(x + 7 ) =54
72 = 8(x-1)
f)98=7 ( x + 4 )

Answer 1

1.

39=5x-1
39+1=5x
40=5x
X=40:5
X=8

73=10x+23
73-23=10x
50=10x
X=50:10
X=5

90=14x-8
90+8=14x
98=14x
X=98:14
X=7

2.

3(X-1)=15
3x-3=15
3x=15+3
3x=18
X=18:3
X=6

5(x+2)=20
5x+10=20
5x=20-10
5x=10
X=10:5
X=2

4(X-7)=28
4x-28=28
4x=28+28
4x=56
X=56:4
X=14

6(x+7)=54
6x+42=54
6x=54-42
6x=12
X=12:6
X=2

72=8(X-1)
72=8x-8
72+8=8x
80=8x
X=80:8
X=10

98=7(X+4)
98=7x+28
98-28=7x
70=7x
X=70:7
X=10

Answer 2

39=5x-1
5x=39+1
5x=40
x=40:5
x=8
73=10x+23
10x=73-23
10x=50
x=50:10
x=5
90=14x-8
14x=90+8
x=98:14
x=7
2)
3(x-1)=15
3x-3=15
3x=15+3
x=18:3
x=6
b)
5(x+2)=20
5x+10=20
5x=20-10
x=10:5
x=2
c)
4(x-7)=28
4x-28=28
4x=28-28
x=0
d)
6(x+7)=54
6x+42=54
6x=54-42
x=12:6
x=2
e)
72=8(x-1)
72=8x-8
8x=72+8
x=80:8
x=10
f)
98=7(x+4)
98=7x+28
7x=98-28
x=70:7
x=7