Armando's workouts consist of kickboxing and swimming. While kickboxing, he burns 10 calories per minute and he burns 9 calories a minute while swimming. He wants to burn at least 450 calories each day.

a) If
x
is the number of minutes that Armando will kickbox and
y
is the number of minutes he will swim, write an inequality that would help Armando create a workout for today.