Răspuns :
Salut,
9 × 7 - n = 7 × 8
63 - n = 7 × 8
63 - n = 56
n = 63 - 56
n = 7✔
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6 × 8 + a = 9 × 10 - 27
48 + a = 90 - 27
48 + a = 63
a = 63 - 48
a = 15✔
9 × 7 - n = 7 × 8
63 - n = 56
n = 63 - 56
n = 7
6 × 8 + a = 9 × 10 - 27
48 + a = 90 - 27
48 + a = 63
a = 63 - 48
a = 15
63 - n = 56
n = 63 - 56
n = 7
6 × 8 + a = 9 × 10 - 27
48 + a = 90 - 27
48 + a = 63
a = 63 - 48
a = 15