Question

a*8+15=79
a*9 -211=60

Answer 1

$a \times 8 + 15 = 79 \\ 8a = 79 - 15 \\ 8a = 64 \\ a = 64 \div 8 \\ a = 8$

$a \times 9 - 211 = 60 \\ 9a = 60 + 211 \\ 9a = 271 \\ a = 271 \div 9 \\ a = 30.(1)$