Cooper is deciding between two truck rental companies. company a charges an initial fee of $80 for the rental plus $2 per mile driven. company b charges an initial fee of $45 for the rental plus $3 per mile driven. let aa represent the amount company a would charge if cooper drives xx miles, and let bb represent the amount company b would charge if cooper drives xx miles. write an equation for each situation, in terms of x,x, and determine the interval of miles driven, x,x, for which company a is cheaper than company b.