Question

Afla numărul necunoscut: a+9x(7+2)=109+8x9 a-(133-8x9)=3x9+4x9 456-(214+9x7)-a=6x9 9x5+8x8+a=214​

Answer 1

a + 9 × ( 7 + 2 ) = 109 + 8 × 9

a + 9 × 9 = 109 + 72

a + 81 = 181

a = 181 - 81

a = 100

a - ( 133 - 8 × 9 ) = 3 × 9 + 4 × 9

a - ( 133 - 72 ) = 27 + 36

a - 61 = 63

a = 63 + 61

a = 124

456 - ( 214 + 9 × 7 ) - a = 6 × 9

456 - ( 214 + 63 ) - a = 54

456 - 277 - a = 54

179 - a = 54

a = 179 - 54

a = 125

9 × 5 + 8 × 8 + a = 214

45 + 64 + a = 214

109 + a = 214

a = 214 - 109

a = 105