Question

rezolvati in R ecuatiile in necunoscuta x, a) 5x+2=3x-7, b)25(x+23)+6=32(x-2)+11, c)2(5x-4)=7(2x-3), d) (2x-3)(3x+4)=(x+7)(6x-8)+3

Answer 1

Răspuns:

a) 5x+2=3x-7

5x-3x=-7-2

2x=-9

x=-9/2

b) 25(x+23)+6=32(x-2)+11

25x+575+6=32x-64+11

25x-32x=-64+11-575-6

-7x=-634 | *(-1)

7x=634

x=634/7

c) 2(5x-4)=7(2x-3)

10x-8=14x-21

10x-14x=-21+8

-4x=-13 |*(-1)

4x=13

x=13/4

d)(2x-3)(3x+4)=(x+7)(6x-8)+3

2x*3x+8x-9x-12=x*6x-8x+42x-56+3

6x^2-x-12=6x^2+34x-53

Reducem termenii asemenea, adica 6x^2

-x-34x=12-53

-35x=-41 |*(-1)

35x=41

x=41/35