Question

5•(x+3)=3•(x-5)
c)2•(-x+4)=-3•(x+1)+23
d)1-2•[3-(4-x)]=-7
e)2•(x+6)-(5-3•x)=2•(-x+9)+3
f)225:(x-3)=-15

Answer 1

Răspuns:

5•(x+3)=3•(x-5)

5x+15=3x-15

5x-3x= -15-15

2x= - 30 /:2

x= - 15

c)2•(-x+4)=-3•(x+1)+23

-2x+8= - 3x-3+23

-2x+3x=20-8

x=12

d)1-2•[3-(4-x)]=-7

1-2×(3-4+x)= - 7

1- 6+8-2x= -7

3-2x= - 7

3+7=2x

10=2x /:2

x=5

e)2•(x+6)-(5-3•x)=2•(-x+9)+3

2x+12-5+3x= - 2x+18+3

5x+7= - 2x+21

5x+2x=21 - 7

7x=14 /:7

x= 2

f)225:(x-3)=-15

225/ x-3= - 15

225= -15(x-3)

225= - 15x+ 45

225-45= - 15x

180= - 15x /:(-15)

x= -12

Explicație pas cu pas: