Answer:
1) 5 2) 6 3) 1.25 or -1.75
Step-by-step explanation:
1. x^2 - 25 = 0
x^2 - 25 = 0
First, add 25 to both sides!
x^2 = 25
Now square root both sides.
x = 5
2. (x-2)^2 = 16
First, square root both sides.
(x-2) = 4
Add 2 on both sides.
(x) = 6
x = 6
3. Quadratic Formula = -b ± 
/ 2a
Substitute in:
-6 ±
/ 2(2)
-6±
/ 4
Both forms:
-6 + 
/ 4
5 / 4 = 1.25
Negative:
-6 - 1 / 4
-7 / 4 = -1.75
The picture is too blurry to read.
The correct answer is it is a figure with at least 3 straight sides. When you think of a square or a triangle they both have at least 3 sides that are straight. A circle doesn't have any straight sides so it is not a polygon.
You can prove that the other answer is wrong because of two things:
The definition of a polygon is a plane figure with at least three straight sides.
Also, when you think of most shapes what do they all have in common? The have at least three straight sides
Explanation
We are asked to give a counter-example for the given statement
A counter-example is an example that opposes or contradicts an idea or statement.
Therefore, for the statement
we have that
Statement: If an appliance is used for cooling
Conclusion: then it is a refrigerator
Then, the option that contradicts this, will be a clothes dryer
Because a dryer doesn't cool
Hence, the answer is a cloth dryer
option D
Answer:
So it would takes approximately 6.9 hours to reach 32 F.
Step-by-step explanation:
For this case we have the following differential equationÑ
We can reorder the expression like this:
We can use the substitution 
and 
so then we have:
IF we integrate both sides we got:
If we apply exponential in both sides we got:
And if we replace w = u-T we got:
We can also express the solution in the following terms:
For this case we know that 
since w ehave a cooloing, 
, we have this model:
And if we want that the temperature would be 32F we can solve for t like this:
If we apply natural logs on both sides we got:
So it would takes approximately 6.9 hours to reach 32 F.
