Question

Oblicz i sprawdż:

a) 0,2*(10-5x)=3+2*(x-1)

b) 8a+4=36

c) -2,5x-8=17

DAJE NAJ!!!

Answer 1

a)  0,2 *( 10 -5x) = 3 + 2 * (x-1)

      2 - x = 3 + 2x -2

      -x -2x = 3 -2 -2 

         -3x = -1 /:(-3)

            x = 1/3

spr.

L = 0,2 *( 10 - 5*1/3) = 0,2 * ( 10 - 5/3) = 0.2 *(30/3 -5/3) = 1/5 * 25/3= 1/1 *5/3 = 5/3

P = 3 + 2( 1/3 - 1)= 3+ 2(1/3 -3/3) = 3 +2 * (-2/3) = 3 +(-4/3) = 9/3 - 4/3 = 5/3

L = P

 

b) 8a +4 = 36

     8a = 36 - 4

     8a = 32/:8

       a = 4

spr.

L = 8 * 4 +4 32 +4 = 36

P = 36

L = P

 

c) -2,5x  - 8 = 17

     -2,5x = 17 +8

     -2,5x = 25 /:(-2,5)

        x = - 10

spr.

L = -2,5 * (-10) -8 = 25 -8 = 17

P = 17

L = P