Equations in Quadratic Form

1.  Solve:  (x + 5)² - 7(x + 5)  + 12  =  0.

 x = {-2, -1}

 u = {3, 4}

 x = 5

2.  Solve:   x⁴ - 6x² - 7  =  0.

  x = {i, -7, 7}

  x = {-7, -1, 1, 7}

  x = {1, 7}

3.  Solve:    x⁶ - 2x³ + 1  =  0.

  x = 1

  x = {-1, 1}

  x = 1,

4.  A ball is tossed into the air with a velocity of 5 ft per second from the top of a building 80 feet high.  The time it takes for the ball to hit the ground (which is 0 ft) is given by the formula

Use your calculator to solve this formula for t.

 t -2.09 seconds

 t 2.4 seconds

 t cannot be determined

5.  A ball is tossed into the air with a velocity of 7 feet per second from the top of a building 98 feet high.  The time it takes for the ball to hit the ground is given by the formula

Use your calculator to solve this formula for t.

 t 2.70 or - 2.27

 t - 2.27

 t 2.70