Ecuații:
x+7=9=>x=9-7=2
x-3=7=>x=7+3=10
x-8=5=>x=5+8=13
x+2=7=>x=7-2=5
14+3x=31=>x=31-14=17
21-x=12=>-x=12-21=-9=>x=9
43+x=-1=>x=-43+1=-44
39-x=-6=>x=-39-6=-45
2x+1=4=>2x=-1+4=3
[tex] \frac{2x}{2} = \frac{3}{2} = > x = \frac{3}{2} [/tex]
4x+2=7=>4x=-2+7=5
[tex] \frac{4x}{4} = \frac{5}{4} = > x = \frac{5}{4} [/tex]
Inecuații:
x-5<7
x<7+5
x<12
-x-7>-2
-x>-2+7
-x>5
x<-5
4-x>12
-x<12-4
-x<8
x>-8
x-2≤3
x≤3+2
x≤5
-x+13≥5
13-x≥5
-x≥5-13
-x≥-8
x≤8
4x+2>6
4x>6-2
4x>4
x>1
2x-5<3
2x<3+5
2x<8
x<[tex] \frac{8}{2} [/tex]
x<4
6+x>9
x>9-6
x>3
-4x-15>5
-4x>5+15
-4x>20
[tex]x \: < - \frac{20}{4} [/tex]
x<-5
8-7x<15
-7x<15-8
-7x<7
x>-1
