Răspuns:
Explicație pas cu pas:
a)5/4=10/(x-1), 5(x-1)=5×10, 5x-5=40, 5x=40+5, 5x=45, x=45:5, x=9
Proportia este 5/4=10/8
b)4=3•(x+1)-5, 4=3x+3-5, 4-3+5=3x, 6=3x, x=6:3, x=2
Verificare
4=3×3-5, 4=9-5, 4=4 (A)
c)|2x-5|=1,
● 2x-5=1, 2x=1+5, 2x=6, x=6:2, x=3
Verificare 2×3-5=1, 6-5=1, 1=1 (A)
● -2x+5=1, 5-1=2x, 4=2x, x=4:2, x=2
Verificare
|2×2-5|=1, |4-5|=1, |-1|=1, 1=1 (A)
