Răspuns :
[tex] \frac{8+x}{2} = 15 =>\\8+x=15*2 \\ 8+x = 30 \\ x=30-8 \\
x=22 [/tex]
Proba
[tex] \frac{8+22}{2} = 30 : 2 = 15 [/tex]
Proba
[tex] \frac{8+22}{2} = 30 : 2 = 15 [/tex]