The larger of two numbers is five more than six times the smaller number. the sum of the numbers is fifty-four

The two numbers are 9 and 45. It's mostly just educated guessing- you start with a random number like 10 and multiply that by 5 which is fifty. 10+50= 60 which is too big. Because it's too big, but still close to the number you want you go down one number. Nine. Nine times five is 45. 45 + 9= 54

1.17+3.99a. you combine the terms with a to create 3.99 and the 1.17 stays because it has no like terms or a variable