Answer to Question #243227 in Math for Anu

Question

5) A civil engineer found that the durability d of the road, she is laying depends on two functions y, and y2 as follows: d = y_{2} ^ 2 + 4y_{1} - 21 Functions y, and yo depend on the amount of plastic (r) mixed in bitumen, and their variations are linear functions of z. Let y = 8 and y_{2} = 3 for x = 0 and y_{1} = 0 and y_{2} = 7 for x = 7 Find the durability of the road (upto 2 decimal points), if the amount of plastic is such that both the functions are equal