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:
