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
 
        
             
        
        
        
"She needs 1.5 cups of flour for 1 batch, but she wants to make 2.5 batches."
This means that she needs 7.5 cups of flour for 5 batches.
Hence, she needs 3.75 cups of flour for 2.5 batches.
        
             
        
        
        
It has to be A I’m sorry if I’m wrong
        
                    
             
        
        
        
Answer:
So put the pi in the 3.14 box then 22/7 to where it says 3.142857143 or something (I can't really see the pic, but yeah that number) then you know the next answer :)
Step-by-step explanation: