Answer:
104°
Step-by-step explanation:
The straight line for
forms an angle of 180°
Therefore,




Answer:
10 < x < 20
Step-by-step explanation:
the sum of any two sides of a triangle has to be greater than the 3rd side, so the maximum value of the third side in this instance is 19.9999999 because 10 + 10 = 20
Answer:

Step-by-step explanation:
So we have the expression:

And we wish to factor it.
First, let's make a substitution. Let's let u be equal to x². Therefore, our expression is now:

This is a technique called quadratic u-substitution. Now, we can factor in this form.
We can use the numbers -3 and -2. So:

For the first two terms, factor out a u.
For the last two terms, factor out a -3. So:

Grouping:

Now, substitute back the x² for u:

And this is the simplest form.
And we're done!
D.A plane consist of an infinite set of lines.