Answer:
16
Step-by-step explanation:
Start by adding 9 to both sides, obtaining: √(x + 9) = 5.
Square both sides, obtaining: x + 9 = 25.
Subtract 9 from both sides: x = 16
Note that √(16+9) - 9 = -4, as required.
Answer:

Step-by-step explanation:
The smallest side of a triangle is formed by the smallest angle in the triangle.
To find the side opposite (formed by) the 20 degree angle, we can use the Law of Cosines. The Law of Cosines states that for any triangle,
, where
,
, and
are the three sides of the triangle and
is the angle opposite to
.
Let
be the side opposite to the 20 degree angle.
Assign variables:
Substituting these variables, we get:

Therefore, the shortest side of this triangle is 3.5.
Answer:
4.39% theoretical probability of this happening
Step-by-step explanation:
For each coin, there are only two possible outcomes. Either it lands on heads, or it lands on tails. The probability of a coin landing on heads is independent of other coins. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
Theoretically, a fair coin
Equally as likely to land on heads or tails, so 
10 coins:
This means that 
What is the theoretical probability of this happening?
This is P(X = 2).


4.39% theoretical probability of this happening
Answer:
-(x-8)*(x+7)
Step-by-step explanation:
Use the commutative property
-× to the power of 2 + x+ 56
-x to the power of 2 + 8x-7x+56
-xx(x-8)-7x+56
-x*(x-8)-7(x-8)
factor out -(x-8)
-(x-8)*(x+7)
hope it helps!!