The following steps are used to rewrite the polynomial expression (x + 4y + 2)(x - 7y).
step 1: x(x – 7y) + 4y(x - 7y) + z(x - 7y)
step 2: x2 - 7xy + 4yx - 28y2 + zx - 7zy
step 3: x2 - 7xy + 4xy - 28y2 + xz – 7yz
step 4: x2 – 3xy - 28y2 + xz - 7yz
identify the property used in each of the steps:
step 1:

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This is the number of parts out of 100, the numerator of a fraction where the denominator is 100. submit

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.