Hello,
which principle?
f(x)=-x²+2x
==>f'(x)= -2x+2
You mean maybe this

f(x+h)=-(x+h)²+2(x+h)= -(x²+2hx+h²)+2x+2h
f(x)=-x²+2x
Answer:
The equation x = y-8
The equation (y-8) y = 240
The first number x = 12 and second number y =20
Step-by-step explanation:
<u>Explanation</u>:-
<u>Step(l)</u>:-
Let 'x' be the first number and 'y' be the second number
Given the product of two numbers is 240
Given data x y = 240 …(l)
Given data the first number is 8 less than the second number.
x = y-8...(ll)
Substitute (ll) in equation (l) , we get
(y-8) y = 240




y = -12 and y = 20
Y= -12 is not satisfied
we can choose y = 20
<u>Step(ll):</u>-
Given data x =y-8
substitute value y = 20 in x = y -8
x = 20-8 = 12
<u>Final answer</u>:-
The first number x = 12 and second number y =20
Step-by-step explanation:
115 = 5x + 15
115 - 15 = 5x
100 = 5x
20 = x
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