Zachary is deciding between two landscaping companies for his place of business. Company A charges $40 per hour and a $100 equipment fee. Company B charges $30 per hour and a $150 equipment fee. Let AA represent the amount Company A would charge for tt hours of landscaping, and let BB represent the amount Company B would charge for tt hours of landscaping. Write an equation for each situation, in terms of t, t, and determine the interval of hours, t, t, for which Company A is cheaper than Company B.