Question

f(x)=sqrt2x-5
find f (7)

A. 2
B. 3
C. -5
D. 7

Answer 1

When they ask you to find f(7) and the equation is
\[\large f(x)=\sqrt{2x-5}\]
f(7) is the form of f(x), so what would the 7 be replacing in f(x)?

Answer 2

@katlin95

Answer 3

oh so 7 would be our answer right?

Answer 4

No...I'm asking you aquestion unrelated to the answer. In maths, I never just go finding the answer in 2 seconds. You need stepping blocks before you can get to the answer...

Answer 5

a question*

Answer 6

yep the 7 would be replacingit

Answer 7

What's "it"?

Answer 8

Is the 7 replacing the moon or something. You're not being specific.

Answer 9

f(x)

Answer 10

f(x) and f(7)...what's the difference between those two figures. I'm just asking you to look at it as a picture and you're trying to spot the difference. what's different. Is the letter f different to each other, are the brackets different? What's different between f(x) and f(7)?

Answer 11

That's a very straight forward question for children under 7. You should be able to get this in a flash.

Answer 12

7 replaces x

Answer 13

Excellent.

Answer 14

So \[\large f(7)=\sqrt{2(7)-5}\]

Answer 15

That's in the form of this
\[\large f(x)=\sqrt{2x-5}\]
Correct?

Answer 16

yep

Answer 17

Everytime you see the term x, you sub in 7. So now could you just calculate the number that's inside the sqrt sign for me?

Answer 18

i got 2x-5 still

Answer 19

We're using this... -_-...
\[\huge f(7)=\sqrt{2(7)-5}\]
Does the question say find f(x)...Because if says that, then it's like child's play. You would just be rewriting what the question gave you...You must pay attention to detail and everything that's related to the QUESTION. The QUESTION in every single subject is like the holy bible in religious terms. The question is the key to everything you do to work out the answer.

Answer 20

3

Answer 21

Correct. Good job. Remember that important basic: read the question. People make mistakes because they're too lazy to read the question. It's that simple. People smart enough to just focus on the question and what it's asking you to do, would obviously be the one's getting top marks.

Answer 22

yay!