Question

**GIVING MEDAL**



What is f(-5) if f(x) = |2x - 1| + 10?

21
19
-1
-21

Answer 1

f is the name of the recipe
x is the ingredient

|x + 1|
is the set of instructions (what to do with the ingredient)

In this case, it says:
take the ingredient (x),
add 1 to it (x+1),
then remove the sign
(that is what the vertical bars say: it is called an "absolute" sign, and it tells you to drop the sign of whatever is inside).
| -7 | = 7
| + 14 | = 14

| square root of 4 | = 2
(without the bars, the square root of 4 COULD be -2, because (-2)(-2) = 4,
but with the vertical bars, you are forced to use only the non-negative value)

---

f(-5)
is a shorthand way of saying:

Use the recipe called "f"
and use "-5" as the ingredient:

Take the ingredient: -5
add 1 to it: -5 + 1 = -4
remove the sign |-4| = 4

Answer 2

@angeleye
I understand what you're saying, but is 4 the outcome or is it the beginning of finding the answer?

Answer 3

@austinL
@JjJustin
please help if you can!

Answer 4

hi,,"
just use this...
the basic meaning of |2x - 1| is....
u will use -(2x -1) instead of |2x - 1| if "x is lesser than 1/2
and
u will use (2x -1) instead of |2x - 1| if "x" is larger than or equal to 1/2

so...........
when u need to find f(-5) u need to substitute (-5) instead of "x" in f(x)
but when
x = (-5) in f(x) x become lesser than 1/2
so...
u will have to change f(x) in to..
|2x - 1| + 10 ----> -(2x -1) + 10 according to the rule above
now u can substitute (-5) instead of "x" in
-(2x -1) + 10

which is..
-{ [2*(-5)] - 1} +10
now ... wt is ur answer bro ?

Answer 5

@***[ISURU]***
My answer then would be 19?

Answer 6

c'mon its easy just plug the values

after putting x=-5 what we get?

|2(-5)-1|+10

|-10-1|+10

|-11|+10=21 where are you having problem?

Answer 7

nope...
-{ [2*(-5)] - 1} +10
- ( -11) +10
11 + 10
wt is ur answer now ?

Answer 8

\(f(x)=|2x-1|+10\)

\(f(-5)\) means that we will merely input "-5" for all instances of "x" in the function.

\(f(-5)=|2(-5)-1|+10\Rightarrow~|-10-1|+10\)

\(|-10-1|=|-11|\Rightarrow~11\)

So therefore we have,

\(f(-5)=11+10+~?\)

Answer 9

\(\color{red}{\text{Correction}}\)
\(f(-5)=11+10=~?\)