M is directly proportional to r^2? When r = 5, M = 200
a) Work out the value of M when r = 3.
b) Work out the value of r when M = 288.​

Three students each examine the system of linear equations shown. 8x + 4y = 16 8x + 2y = 8 caleb says there is exactly one solution. jeremy says there is no solution. kim says there are infinitely many solutions. which student is correct? provide mathematical reasoning to support your answer. answer in complete sentences. : d

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?

Your vet has placed your pet on a diet. the diet is to contain at least 12 mg of fat and at least 14 mg of protein per serving. these requirements are to be obtained from two food sources. source a contains 2 mg of fat and 2 mg of protein per serving. source b contains 1 mg of fat and 3 mg of protein per serving. if source a sells for $1.28 per serving and source b sells for $1.12 per serving, how many servings of each type should be purchased to satisfy the requirements at minimal cost?