Step-by-step explanation:
1. The equation graph is a parabola, so the maximum height will be the vertex of the parabola. You can find the vertex coordinate t using the formula:
t = -b/2a
t = -18/2•(-4.9)
t = -18/-9.8
t = 1.84 seconds
2. The height of the ground is 0, so the balls hit the ground when the equation result is 0:
0 = -4.9t²+18t+10
Now you solve it using Bhaskara:
Δ = b² -4ac
Δ = 18² -4•(-4.9)•10
Δ = 520
t = (-b ±√Δ)/2a
t = (-18 ± √520)/2•(-4.9)
t1 = (-18 - 20.8)/-9.8
t1 = 3.96 seconds
t2 = (-18 +20.8)/-9.8
t2 = -0.28
Doesn't exist negative time, so we pick the first value found, t = 3.96 seconds
3. Now you just need to put 3 in place of t to find the result:
h = -4.9•3² +18•3 +10
h = -4.9•9 + 54 + 10
h = -44.1 + 64
h = 19.9 meters
4. You just need to put 1 in place of t to find the height:
h = -4.9•1²+12
h = -4.9+12
h = 7.1 meters
Answer:
See below.
Step-by-step explanation:
Let the smaller integer be n.
Then the larger integer is n + 2.
"When the smaller integer is added to three times the larger integer, the result is two less than five times the smaller integer."
The correct equation is:
n + 3(n + 2) = 5n - 2
His mistake is not using parentheses on the left side. Since he left out the parentheses, the left side is not "the smaller integer added to three times the larger integer", but rather it is "the smaller integer added to 2 plus 3 times the smaller integer."
n + 3(n + 2) = 5n - 2
n + 3n + 6 = 5n - 2
4n + 6 = 5n - 2
8 = n
n = 8
n + 2 = 10
The integers are 8 and 10.
