SOLVE EACH SYSTEM BY SUBSTITUTION MUST SHOW YOUR WORK. THIS IS FOR TODAY I NEED ITS ASAP

Acontractor needs 54 square feet of brick to construct a rectangular walkway. the length of the walkway is 15 feet more than the width. write an equation that could be used to determine the dimensions of the walkway. solve this equation to find the length and width, in feet, of the walkway.

What are the solutions of the equation? 16x^2 + 24x + 5 = 5 a. 1/4, 5/4 b. -1/4, -5/4 c. -1/4, 5/4 d. 1/4 , -5/4

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?