Question

a)
(2x-4):2 mai mic sau egal cu 2
b)
{5•[3•(2x-8)-8 ]-8}:4=3

Answer 1

a) (2x-4):2<\ 2

2x+4<\ 2×2

2x+4<\ 4

2x<\ 4-4

2x<\ 0

x<\ 0

x aparţine (-infinit, 0]

b) {5×[3×(2x-8)-8]-8}=12

5×[3×(2x-8)-8]-8=12

5×[3×(2x-8)-8]=20

3×(2x-8)-8=5

3×(2x-8)=13

2x-8=13/3

2x=13/3+8 amplifici pe 8 cu 13

2x=13/3+104/13

2x=117/3

x=117/3×1/2

x=117/6