Question

Rezolvati, in mulţimea numerelor reale, ecuațiile a) 4x-1=x+8; b)x - 2 = 3x + 6; c) 5 - 2x = x - 4; d) 4-5x =7 - 2x. ​

Answer 1

Răspuns:

a) 4x-1 = x+8

4x = x+8+1

4x-x = 8+1

3x = 9

x = 9÷3 = 3

b) x-2 = 3x+6

x= 3x+6+2

x = 3x + 8

x-3x = 8

-2x = 8

x = 8÷(-2) = -4

c) 5-2x = x-4

-2x = x-4-5

-2x = x-9

-2x-x = -9

-3x = -9

x = (-9)÷(-3) = 3

d) 4-5x = 7-2x

-5x = 7-2x-4 = -2x + 7 - 4

-5x = -2x + 3

-5x + 2x = 3

-3x = 3

x = 3 ÷ (-3) = -1