Question

Sa se rezolve in Z ecuatiile; a) 9-2x=-21-7x . b) 3(x+1)=11-x . c)3x+2=3(x+1) . d) 5+x-2=-x+3 . e)2(x+1)=10-x Va rog imi trebuie la sch..

Answer 1

a). 9-2x=-21-7x
-2x+7x=-21-9
5x=-30
x=-6 apartina Z

b). 3x+3=11-x
3x+x=11-3
4x=8
x=2 apartina Z

c).3x+2=3x+3
3x-3x=3-2
0=1 nu are sens

d). 5+x-2=-x+3
x+x=3+2-5
2x=0
x=0 apartine Z

e).2x+2=10-x
2x+x=10-2
3x=8
x=8/3 nu apartine Z

Answer 2

a)
$9-2x=-21-7x$
$-2x+7x=-21-9$
$5x=-30$
$x=-6$ ∈ Z
b)
$3x+3=11-x$
$3x+x=11-3$
$4x=8$
$x=2$ ∈ Z
c)
$3x+2=3x+3$
$3x-3x=3-2$
$0=1 (F)$ ==>Ø
d)
$5+x-2=-x+3$
$x+x=3-5+2$
$2x=0$
$x=0$ ∈ Z
e)
[tex]2x+2=10-x [/tex]
$2x+x=10-2$
$3x=8$
$x= \frac{8}{3}$ ∉Z