Question

if f(x)=(x^2) -1, and f(2a)=35, then what could be the value of a?

Answer 1

Can you post a picture of this or dont copy and paste stuff since it doesn't make sense.

Answer 2

@Anikate

Answer 3

@Austin1617 its #4

Answer 4

the answer is not B btw

Answer 5

f(x) = 6^2 -1

f(x)=36-1

f(x) =35

Answer 6

So E @Anikate

Answer 7

why??

Answer 8

oh ok wait

Answer 9

where did u get 6 from??

Answer 10

f(x)=(x^2) -1 is the given function.

Substitute (2a) for x, on both sides.

Please show your work.

Answer 11

I did simple math and 6 power of the 2 equals 36 then minus 1

Answer 12

sorry, still trying to understand this

Answer 13

sustitute 2a on both sides and what?

Answer 14

f(x)=(x^2) -1 is the given function.

Substitute (2a) for x, on both sides.

Please show your work. Simplify your results as much as you can.

Answer 15

I'm asking you to replace each "x" with "(2a)"

Answer 16

f(x)=(x^2) -1 is the given function. Eliminating the "x" results in f( ) = ( )^2 - 1.

Substitute (2a) into the each set of parentheses on both sides.

Please show your work.

Answer 17

I need your pretty much constant attention if you want to solve this problem.

Answer 18

ok yea i see

Answer 19

f(x)=(x^2) -1 is the given function. Eliminating the "x" results in f( ) = ( )^2 - 1.

Substitute (2a) into the each set of parentheses on both sides.

Answer 20

ok done

Answer 21

now?

Answer 22

Type out your result, and then we'll discuss what to do next.

Answer 23

f(2a)=(2a)^2 -1

Answer 24

Good. Evaluate (2a)^2 now, please. Then, subtract 1 from your result.

Answer 25

What do you mean by evaluate? what do i plug i for a? @mathmale

Answer 26

Evaluate = find the value of ...

This is algebra, so you need to become used to working with unknown quantities represented by letters, such as " a ".

You don't plug in some value for " a ". .... Rather, you FIND the value of a.

f(2a) = (2a)^2 - 1 = 35 (as given in the original problem statement).

Please evaluate (find the equivalent expression of ) (2a)^2.

Answer 27

f(2a) = [ ? ] - 1 =35

Answer 28

ooh ok so then a=(plus or minus) 3

Answer 29

a= 3 root 2

Answer 30

I'd prefer to see all of your work, not just what you think the answer is.

f(2a) = 4a^2 - 1 = 35. What did you do next?

Answer 31

add 1 to both sides, then divide by 4, so then u would get a^2 = 9, then a=3

Answer 32

Right. Actually, a could be either 1) a=3 or 2) a=-3; both will satisfy the original equation.

Answer 33

-3 is the answer? but I was told that is wrong. its ok, I have to go to sleep now anyways, i'll double check with my instructor tomorrow

Answer 34

You yourself could substitute a=-3 into the original equation.
Then (2a)^2 = (2)^2 * (-3)^2 = +4(+9).