Answer:
f(- 4) = 12
Step-by-step explanation:
To evaluate f(- 4) substitute x = - 4 into f(x) , that is
f(- 4) = - 8 - 5(- 4) = - 8 + 20 = 12
When finding the mean you should first add up all the numbers which are 12,2,8,6 and 57 which will give you a sum of 85 next you should divide your sum by how many numbers there are which is 5 and your answer should be 17
Answer:
x = 3
Step-by-step explanation:
(x - 1)2 = 4
how to get this solved is very simple.
first step to apply is the BODMAS RULE
B..................... bracket
O..................... of
D.....................Division
M.................... multiplication
A..................... addition
S.................... Subtraction
so (x - 1)2 = 4
we have,
2x - 2 = 4 ( by opening the bracket)
collect the like terms
2x = 4+2
divide both sides by 2
2x/2 = 6/2
x = 3
to check if your answer is correct put the value of x = 3 into the question and see if the right hand side will equal to the left handside
(x - 1)2 = 4
(3-1)2=4
2(2)=4
4=4.............................. proved
Answer:

Step-by-step explanation:
We know:

We have

Use 
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Answer:
8.4
Step-by-step explanation:
42÷5
then just multiply your answer to 5 to see if it is right