7x to the 3 power + x-2x to the 3 power + 5x + 8

Place the following steps in order to complete the square and solve the quadratic equation,

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.