Please refer to the attachment for the answer and explanation. Hope it helps!!
F'(x) = 7sec x . tan x - 5.
Hello :
<span> y=-6(2.5-x)(x-5.5) = -6(2.5x -13.75 -x² +5.5x)
y = -6(-x²+8x -13.75)
y = 6x²-48x+82.5
note :
if f(x) = ax²+bx +c the vertex is the point : ( -b/2a ; f(-b/2a))
a=6 b=-48 c = 82.5 .......calculate
-b/2a = -(-48)/2(6)= 4
f(4) =6(4)²-48(4)+82.5 =96 - 192 +82.5 = -13.5</span>
Answer:

Step By Step Explanation:
Follow PEMDAS Order Of Operations
Calculate Within Parenthesis: 

Calculate Exponents: 

Divide: 

Add

➤ 
Answer:
2.30*3=6.90
6.90+2.30=9.20
Step-by-step explanation: