Answer:
$21
Step-by-step explanation:
Add what she spent to what she has left.
Answer:
-2x² + 15
Step-by-step explanation:
Step 1: Add like terms
4x² - 6x² = -2x²
-10x + 10x = 0
3 + 12 = 15
Step 2: Rewrite
-2x² + 15
Multiply 9 books by 55% by doing
9 x .55 = 4.95
We can't have 4.95 books, though so it rounds down to 4 because you can't just add another .05.
Using the product rule, we have

so that

The equation of the tangent line to <em>W(x)</em> at <em>x</em> = 7 has all the information we need to determine <em>m'</em> (7).
When <em>x</em> = 7, the tangent line intersects with the graph of <em>W(x)</em>, and
<em>y</em> = 4.5 + 2 (7 - 7) ==> <em>y</em> = 4.5
means that this intersection occurs at the point (7, 4.5), and this in turn means <em>W</em> (7) = 4.5.
The slope of this tangent line is 2, so <em>W'</em> (7) = 2.
Then

Answer:
n < -10
Step-by-step explanation: