Question

va rog am nevoie repede până la prânz ajutor ofer coroană
ps fără ex 5​

Answer 1

Răspuns:

1)a) 5x-2= -7

5x= - 7+2

5x= - 5

x= - 1

b) 4-2,3x = - 0,6

4-23/10x= - 6/10

-23/10x= - 6/10- 4

-23/10x= (-6-40)/10

-23x/10= - 46/10 /×10

-23x= - 46 /:(-23)

x= 2

c) (radical 2)+2x= radical 18

(rad2) +2x= rad( 3^2×2)

(rad2)+2x= 3( rad2)

2x= 3(rad2)-(rad2)

2x= 2 (rad 2) /:2

x= rad 2

2)

3(x-3)-2(1-x)= 2x-2(x+4)+7

3x-9-2+2x= 2x-2x-8+7

5x-11= 0x-1

5x=-1+11

5x= 10 /:5

x= 2

3)

(-2x-1)-4x+6 = - 2x^2+9-8x

-2x-1-4x+6= - 2x^2+9-8x

-6x+5 = - 2x^2+9-8x

2x^2+8x-6x-9+5=0

2x^2+2x-4=0 /:2

x^2+x-2=0

Scrie x ca o diferență :

x^2+2x-x-2=0

x(x+2)-x-2=0

x(x+2)-(x+2)=0

(x+2)(x-1)=0

x+2=0

x 1 = - 2

Sau

x-1=0

x 2 = 1

Solutiile sunt :

x 1 = - 2

x 2= 1

4)

(4x-5) /14= 3/14+ (x-1) /2+ (2x+3) / 7

Aducem la același numitor comun

(4x-5)/14= 3/14+7(x-1) /14+ 2(2x+3) /14

(4x-5)/14= 3/14+(7x-7)/14+ 4x+6/14

/×14

4x-5= 3+7x-7+ 4x+6

4x-5= 11x+2

4x-11x=2+5

-7x = 7 /:(-7)

x= - 1

Explicație pas cu pas: