Answer:
You did not post the options, but i will try to answer this in a general way.
Because we have two solutions, i know that we are talking about quadratic equations, of the form of:
0 = a*x^2 + b*x + c.
There are two easy ways to see if the solutions of this equation are real or not.
1) look at the graph, if the graph touches the x-axis, then we have real solutions (if the graph does not touch the x-axis, we have complex solutions).
2) look at the determinant.
The determinant of a quadratic equation is:
D = b^2 - 4*a*c.
if D > 0, we have two real solutions.
if D = 0, we have one real solution (or two real solutions that are equal)
if D < 0, we have two complex solutions.
Answer:
The ball will be 84 feet above the ground 1.125 seconds and 4.5 seconds after launch.
Step-by-step explanation:
Statement is incorrect. Correct form is presented below:
<em>The height </em>
<em> of an ball that is thrown straight upward from an initial position 3 feet off the ground with initial velocity of 90 feet per second is given by equation </em>
<em>, where </em>
<em> is time in seconds. After how many seconds will the ball be 84 feet above the ground. </em>
We equalize the kinematic formula to 84 feet and solve the resulting second-order polynomial by Quadratic Formula to determine the instants associated with such height:
(1)
By Quadratic Formula:
, 
The ball will be 84 feet above the ground 1.125 seconds and 4.5 seconds after launch.
4 mountains per month, 48/12
Answer:
x > -1
Step-by-step explanation:
