David purchased some cookies at the cost of 5 for $4 and sold 4 for $5. he made a profit of $90. how many cookies did he purchase and sell to make that much money

Darian wants to build a regulation size pool table that is 9 feet in length.he plans he ordered are 18 by 36 inches. what is the scale factor of the dilation he must use to build a regulation pool table

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

Jeremy wants to determine the number of solutions for the equation below without actually solving the equation.