Solve using cross pruduct: 7/4 = 21/x

Lindsay used two points, (x, y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?

What is the difference between the predicted value and the actual value

Find the maximum value of p= 4x + 5y subject to the following constraints :