11 is the answer.
10+10=20
20-9=11
11+9=20
11
Answer:
8x²- x -8
Step-by-step explanation:
The question is not well written. I guess what you mean is:
Subtract -2x^2+4x-1 ( minus 2x squared plus 4x minus 1) from 6x^2+3x-9 (6x squared plus 3x minus 9).
To subtract -2x^2+4x-1 from 6x^2+3x-9, that is
6x^2+3x-9 - (-2x^2+4x-1). This can be written as
6x²+3x-9 - (-2x²+4x-1)
Now, opening the bracket, we will get
6x²+3x-9 +2x²-4x+1
Then, collecting like terms, we get
6x²+2x²+3x-4x-9+1
6x²+2x² = 8x²
3x-4x = -x
-9+1 = -8
∴6x²+2x²+3x-4x-9+1 becomes
8x²-x -8
The answer is 8x²-x -8.
Your answers is 30, use this pic to show ur work
9514 1404 393
Answer:
C. 168°
Step-by-step explanation:
The exterior angle at any vertex of an n-gon will be ...
360°/n
So a 30-gon will have exterior angles of ...
360°/30 = 12°
The adjacent interior angle is supplementary to this, so is ...
180° -12° = 168°
_____
<em>Using the reasonableness test</em>
You know that the interior angles of a square are 90°, and that regular polygons with more sides have larger interior angles. The most any regular polygon's interior angle can be is 180°. The only answer choice between 90° and 180° is the correct choice: 168°.

The numbers are 3, 7, and 11.