Answer:
He bought 17 books.
Step-by-step explanation:
Given that:
Total money spent = $89
Cost of each book = $5
Shipping price = $4
We have to find, Total number of books
So if the number of books be represented by b, the equation will become:
Cost of one book * total number of books + shipping price = total money
Putting values we get:
5*b + 4 = $89
By simplifying:
5*b = 89 - 4
5*b = 85
Dividing both sides by 5 we get:
b = 17
So the total number of books bought is 17.
i hope it will help you!
The bird on the roof of a 250 ft building landed on the ground after 25 seconds
<h3>The height of the bird is modelled as follows:</h3>
h(t) = -t² + 15t + 250
h(t) = height of the bird above the ground(ft)
t = time in seconds after leaving the roof.
Therefore, the time in seconds the bird land after leaving the roof can be calculated as follows:
h(t) = -t² + 15t + 250
0 = -t² + 15t + 250
0 = -t² + 15t + 250
t² - 15t - 250 = 0
Using quadratic formula,
a = 1
b = -15
c = -250
t = -b ±√b² - 4ac / 2a
t = -b ± √(-15)² - 4(1)(-250) / 2 × 1
t = 15 ± √225 + 1000 / 2
t = 15 ± √ 1225 / 2
t = 15 ± 35 / 2
t = 15 - 35 / 2 or t = 15 + 35 / 2
t = -20 / 2 or 50 / 2
t = -10 or 25
The time can't be negative.
Therefore, the bird landed on the ground after 25 seconds.
learn more on parabola here: brainly.com/question/24631429?referrer=searchResults
2l+2w=100
2(w+20)+2w=100
2w+40+2w=100
4w+40=100
4w=60
w=15
l=w+20
l=15+20
Greatest length is 35ft.
Answer : 25ft^2
Explanation - A=1/2BH