Carla and Rob left a 20% tip after having lunch at a restaurant. The amount of the tip was $6. Carla's lunch cost $15. Write an equation you can use to find x, the cost of Rob's lunch.

Scarlet bought three pairs of sunglasses and two shirts for $81 and paula bought one pair of sunglasses and five shirts for $105 what is the cost of one pair of sunglasses and one shirt?

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

Do,h = (7, 9) (14, 18) the scale factor is