Question

Rezolvati:
a.5(3x-2)+3x-6(8x-13)=16(9-2x)-78
b.2(3x+4)-5(2x-3)-2=7(2x-4)+2(8-5x)+3x
c.2(3x-4)+5(6x-7)-3x=9(x+10)+11(x+12)+8
d.3(6x-5)-2(4x+3)+13= -2(-4x+9)+2x-5(3x-2)

Va rog

Answer 1

a)

5 ( 3 x - 2 ) + 3 x - 6 ( 8 x - 13 ) = 16 ( 9 - 2 x ) - 78

15 x - 10 + 3 x - 48 x + 78 = 144 - 32 x - 78

18 x - 48 x + 32 x = 66 - 68

2 x = - 2

x = - 1

_____________________

b)

2 ( 3 x + 4 ) - 5 ( 2 x - 3 ) - 2 = 7 ( 2 x - 4 ) + 2( 8 - 5 x ) + 3 x

6 x + 8 - 10 x + 15 - 2 = 14 x - 28 + 16 - 10 x + 3 x

- 4 x - 7 x = - 12 - 21

- 11 x = - 33

x = ( - 33 ) : ( - 11 )

x = 3

________________

c)

2 ( 3 x - 4 ) + 5 ( 6 x - 7 ) - 3 x = 9 ( x +10 ) + 11 ( x + 12 ) + 8

6 x - 8 + 30 x - 35 - 3 x = 9 x + 90 + 11 x + 132 + 8

33 x - 20 x = 230 + 43

13 x = 273

x = 273 : 13

x = 21

_______________

d)

3 ( 6 x - 5 ) - 2 ( 4 x + 3 ) + 13 = - 2 ( - 4 x + 9 ) + 2 x - 5 ( 3 x - 2 )

18 x - 15 - 8 x - 6 + 13 = 8 x - 18 + 2 x - 15 x + 10

10 x + 5 x = - 8 + 8

15 x = 0

x = 0

Answer 2

a)

5(3x-2)+3x-6(8x-13)=16(9-2x)-78

15x-10+3x-48x+78=144-32x-78

-30x+68=144-32x-78

-30x+68=-32x+66

-30x+68+32x=66

2x+68=66

2x=66-68=-2

x=-1

b)

2(3x+4)-5(2x-3)-2=7(2x-4)+2(8-5x)+3x

6x+8-10x+15-2=14x-28+16-10x+3x

-4x+21=14x-28+16-10x+3x

-4x+21=7x-12

21=7x-12+4x

21=11x-12

21+12=11x

33=11x

$\frac{33}{11} = x$

x=3

c)

2(3x-4)+5(6x-7)-3x=9(x+10)+11(x+12)+8

6x-8+30x-35-3x=9x+90+11x+132+8

33x-43=9x+90+11x+132+8

33x-43=20x+230

33x=20x+230+43

33x=20x+273

33x-20x=273

13x=273

$x = \frac{273}{13} = 21$

d)

3(6x-5)-2(4x+3)+13=-2(-4x+9)+2x-5(3x-2)

18x-15-8x+6+13=8x-18+2x-15x+10

10x-8=8x-18+2x-15x+10

10x-8=-5x-8

10x=-5x

-2x=x

0=x+2x

0=3x

x=0