Question

ex.3 începând de la E

Answer 1

e) 2,5x+2 = 4,5x + 6

2,5x - 4,5x = 6-2

-2x = 4

x = -2

f) 7x+5 = -9

7x = -9-5

7x = -14

x = -2

g) v = radical

/ = fractie

(5-v7)x = v28-10

x = v28-10/5-v7

x = 2v7-10/-(v7-5)

x = 2(v7-5)/-(v7-5)

x = 2*(-1)

x = -2

h) 2(2x+7) = 6+3(x+2)

4x+14 = 6+3x+6

4x+14 = 12 +3x

4x=3x = 12-14

x = 12-14

x = -2

i) ^ = putere

(2x+3) * (x+1) = (2x+5) * (x+3)

2x^2+2x+3x+3 = 2x^2+6x+5x+15

2x+3x+3 = 6x+5x+15

5x+3 = 11x+15

5x-11x = 15-3

-6x = 12

x = -2