1.
x + 1 = 1 + 1 + 1
x + 1 = 3
Odp. B.
2.
9x - 6 = 8x + 4
9x - 8x = 4 + 6
x = 10
3.
a)
3x + 4 = 16
3x = 16 - 4
3x = 12 /:3
x = 4
b)
6x - 5 = x + 4
6x - x = 4 + 5
5x = 9 /:5
x = 9/5
x = 1⁴/₅
c)
3(x + 5) = 2x - 4
3x + 15 = 2x - 4
3x - 2x = -4 - 15
x = -19
4.
x - wiek Jurka
x + 6 - wiek brata Jurka
x + x + 6 = 22
2x = 22 - 6
2x = 16 /:2
x = 8 lat → wiek Jurka
x + 6 = 8 + 6 = 14 lat → wiek brata Jurka
Odp. Bracia mają 8 lat i 14 lat.
