To determine when the soccer ball hits the ground, we start with the equation \( -16t^2 + 20t + 3 = 0 \) and use the quadratic formula to solve for \( t \). After calculating the discriminant and simplifying, we find two potential solutions for time: \( t_1 = \frac{5 + \sqrt{37}}{8} \) and \( t_2 = \frac{5 - \sqrt{37}}{8} \). Since time cannot be negative, the soccer ball will hit the ground in approximately 1.39 seconds after being kicked.
To find out when the soccer ball will hit the ground, we need to figure out when its height \( y \) is 0. We start with the equation:
\[
0 = -16t^2 + 20t + 3.
\]
This is a quadratic equation! To make it easier to work with, let's rearrange it to:
\[
-16t^2 + 20t + 3 = 0.
\]
We can multiply everything by -1 to get rid of the negative sign:
\[
16t^2 - 20t - 3 = 0.
\]
Now, we can use the quadratic formula to find \( t \). The quadratic formula is:
\[
t = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a},
\]
where \( a = 16 \), \( b = -20 \), and \( c = -3 \).
### Step 1: Calculate the discriminant
First, let's find \( b^2 \):
\[
b^2 = (-20)^2 = 400.
\]
Next, we need to calculate \( 4ac \):
\[
4ac = 4 \cdot 16 \cdot (-3) = -192.
\]
Now we can find out what's called the discriminant:
\[
b^2 - 4ac = 400 - (-192) = 400 + 192 = 592.
\]
### Step 2: Use the quadratic formula
Now we put our numbers into the quadratic formula:
\[
t = \frac{-(-20) \pm \sqrt{592}}{2 \cdot 16}.
\]
This simplifies to:
\[
t = \frac{20 \pm \sqrt{592}}{32}.
\]
### Step 3: Simplify \(\sqrt{592}\)
Next, we’ll simplify \(\sqrt{592}\):
\[
592 = 16 \cdot 37,
\]
so:
\[
\sqrt{592} = \sqrt{16 \cdot 37} = 4\sqrt{37}.
\]
### Step 4: Substitute back into the formula
Now we have:
\[
t = \frac{20 \pm 4\sqrt{37}}{32}.
\]
We can simplify this a bit more:
\[
t = \frac{20}{32} \pm \frac{4\sqrt{37}}{32} = \frac{5}{8} \pm \frac{\sqrt{37}}{8}.
\]
### Step 5: Calculate the two potential solutions
So, we have two different times:
\[
t_1 = \frac{5 + \sqrt{37}}{8},
\]
\[
t_2 = \frac{5 - \sqrt{37}}{8}.
\]
### Step 6: Find the positive solution
Since time can’t be negative, let’s check which one is positive:
#### Estimating \(\sqrt{37} \approx 6.08\)
1. For \( t_1 \):
\[
t_1 \approx \frac{5 + 6.08}{8} = \frac{11.08}{8} \approx 1.39.
\]
2. For \( t_2 \):
\[
t_2 \approx \frac{5 - 6.08}{8} = \frac{-1.08}{8} \approx -0.135.
\]
Since time can’t be negative, we ignore \( t_2 \).
### Conclusion
The soccer ball will hit the ground in about **1.39 seconds** after being kicked!
make this into 3 sentences
1 answer