Three consecutive numbers such that 9 times the first number equals the third number plus 7 times the second number

Question

The consecutive numbers such that 9 times the first number equals the third number plus 7 times the second number

Answer 1

the 3 numbers are 9,10 and 11

9(9) = 11 +7(10)

81 = 11+70

81 = 81

Let F= First number

S = Second number

T = Third number

S=F+1

T=S+1 = F+2

9F =T+3S

9F =F+2 +7(F+1)

9F = F+2 +7F+7

F = 9

S=10

T=11