Answer:
14 books
Step-by-step explanation:
Let b = number of books at the beginning
She sold 1/2 of the books
b - 1/2 b
This is how many she had left
Then she bought 7
b - 1/2 b + 7
this equals 14
b - 1/2 b + 7 = 14
Combine like terms
1/2 b + 7 = 14
Subtract 7 from each side
1/2 b = 14-7
1/2 b = 7
Multiply each side by 2
1/2 b * 2 = 7*2
b = 14
She started with 14 books
<h3>
Answer is 1.5 square meters</h3>
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Work Shown:
The portion of the fabric that is laying across the ground is 2 meters. The portion of the fabric from the ground to the highest point (along the fabric's edge) is 1.5 meters, half of that is 0.75 meters and this is the length of the shadow. We can see this by forming a 30-60-90 triangle. The hypotenuse is 1.5 meters, the short leg is 0.75 meters. The short leg is always half of the hypotenuse of any 30-60-90 triangle, and the short leg is opposite the 30 degree angle.
So this shadow has length of 2 meters and 0.75 meters, making its area be 0.75*2 = 1.5 square meters when the sun is directly overhead at 12 noon
Answer:
y = 5 e^r * t
Let y be the population in billions and t the value of elapsed years
7 = 5 e^r * t is the equation being used where t = 15
7/5 = e^r * t
ln 7/5 = r * t taking ln of both sides
r = .336 / 15 = .0224
y = 5 e^(.0224 t) is then our equation
Check - suppose you want y at 2020
y = 5 e^(.0224 * 20) would be the equation
y = 5 e^.449 = 7.83 billion - seems to be a reasonable answer
Answer:
49×66+49×34 = 49× (66+34)
The opposite of a nonzero integer is the inverse of it. So to get the opposite, change the sign.
For example:
What's the opposite of 3?
-3.
I hope that I explained well :)
