Is there an a choice ? Or are those all the choices, just making sure
Answer:

Explanation:

simplify the following

subtract 1 from both sides

simplify the following

multiply both sides by 1/3

simplify the following

The tangent line to <em>y</em> = <em>f(x)</em> at a point (<em>a</em>, <em>f(a)</em> ) has slope d<em>y</em>/d<em>x</em> at <em>x</em> = <em>a</em>. So first compute the derivative:
<em>y</em> = <em>x</em>² - 9<em>x</em> → d<em>y</em>/d<em>x</em> = 2<em>x</em> - 9
When <em>x</em> = 4, the function takes on a value of
<em>y</em> = 4² - 9•4 = -20
and the derivative is
d<em>y</em>/d<em>x</em> (4) = 2•4 - 9 = -1
Then use the point-slope formula to get the equation of the tangent line:
<em>y</em> - (-20) = -1 (<em>x</em> - 4)
<em>y</em> + 20 = -<em>x</em> + 4
<em>y</em> = -<em>x</em> - 24
The normal line is perpendicular to the tangent, so its slope is -1/(-1) = 1. It passes through the same point, so its equation is
<em>y</em> - (-20) = 1 (<em>x</em> - 4)
<em>y</em> + 20 = <em>x</em> - 4
<em>y</em> = <em>x</em> - 24
Answer:
2.80
Step-by-step explanation:
The discount is the regular price times the discount
discount = 19 *15%
discount = 2.85
The new price is the regular price minus the discount
new price = 19-2.85
=16.15
Now she has to pay the sales tax
tax = new price * tax rate
tax= 16.15 * 6.5%
= 16.15 *.065
=1.05
We add the tax to the new price to get the final price
final price = new price+tax
= 16.15 +1.05
=17.20
She pays with a 20 dollar bill
Change = payment - final price
=20.00 - 17.20
= 2.80