Answer:
Step-by-step explanation:
If we are given the quadratic model, we know that the height of anything on the ground is 0 meters, so that model becomes
I changed your x's to t's since t is for time.
Now we need to factor that quadratic and solve for time:

Since -2 definitely does not equal 0, then

Factor that and find t values of 4 and -2. Again, we know that time will never be negative, so
t = 4 seconds.
S= 15
3s=45
3s/3=45/3
S=15
You have to divide both sides
Answer:
The correct answer is <em>b = 36</em>
Step-by-step explanation:
In order to find out what b is, you must find out what 9/10 is.
9/10 is 0.9. This will later be used to check our answer.
Now, solve by using cross-multiplication
b * 10 = 9 * 40.
Then use the commutative property to reorder the terms
10b = 9 * 40
Now Multiply 9 * 40 = 360
10b = 360
Now divide both sides of the equation by 10
<em>b = 36</em>