999999%
Step-by-step explanation:
Answer:

Step-by-step explanation:
Look at the picture.
ΔADC and ΔCDB are similar. Therefore the sides are in proportion:

We have

Substitute:
<em>cross multiply</em>


For x use the Pythagorean theorem:

Answer:
The third choice: (x² - 1)³
Step-by-step explanation:
That is the only expression that is a binomial. Binomial means "two numbers". For this expression, x² is one number, and -1 is the other. Choice 1 is a monomial (one number) and choices 2 and 4 are trinomials (three numbers)
Answer:
29
Step-by-step explanation:
Well "value" of 3x^2 - 7x + 9 when x = 4 is just x plugged into the expression
3 * 4^2 - 7 * 4 + 9
3 * 16 - 28 + 9
= 29
Answer:
x>-4
Step-by-step explanation:
13-2x > 21
-13 -13
-2x >8
(-2x)/(-2) >(8)/(-2)
x>-4