Question

Buna! Ma poate ajuta cineva ??? Va rog din suflet !!!!!​

Answer 1

2

a)

x-3=-1 <=> x=-1+3 <=> x=2

b)

2x+7=3 <=> 2x=3-7 <=> 2x=-4 <=> x=-2 (Banuiesc ca e ceva greseala aici, ca nu apare -2, iar celelalte valori nu verifica ecuatia)

c)

-3x+1=-5 <=> -3x=-6 <=> x=2

d)

2-2x=4 <=> -2x=4-2 <=> -2x=2 <=> x=-1

Answer 2

a. x-3= -1,x∈{-1,0,1,2,3}

x= -1+3

x=2∈{-1,0,1,2,3}

b. 2x+7=3,x∈{-1,0,1}

2x=3-7

2x= -4

x= -4:2

x= -2∉{-1,0,1}⇒ x∈∅

c. -3x+1= -5,x∈{-2,-1,0,1,2,3}

-3x= -5-1

-3x= -6

3x=6

x=6:3

x=2∈{-2,-1,0,1,2,3}

d. 2-2x=4,x∈{-3,-2,-1}

2x=2-4

2x= -2

x= -2:2

x= -1∈{-3,-2,-1}