Question

Aflati nr nat x: dau coroana

a) 5+2(2x+1)=5(x-1)

b)15x+5<10x+25=
ajutor

Answer 1

a) 5+2(2x+1) = 5(x+1)

5+4x+2 = 5x+5

5x - 4x = 7 - 5 , x = 2

Verificare : 5+2(2*2+1) = 5(2+1), 15 =15 (A)

b) 15x +5<10x + 25

15x-10x < 25 - 5

5x < 20, x<20:5, x<4

x apartine multimii {0,1,2,3}

Answer 2

5+4x+2 = 5x-5
5+2+ 5=5x-4x
x=12
b) 
15x+5 m.m. 10x +25         ,x apartine(0,1,2,3)
15x-10x m.m. 25-5
5x m.m. 20
x m.m. 4
V:15 ori 4 +5 m.m. 10 ori 4+25
60 +5 m.m40+25
65 m.m. 65