Question

FAN AND MEDAL!!!



Given f(x) = X+7/5, solve for f-1(3).

Answer 1

ii. Rewrite -3x + 4y = 11 as a function of x. You must solve the given equation for y, since y = f(x).
then (3x + 11)/4 = y gives f(x) = (3x + 11)/4.
iii. Graph the function using the intercepts : y-intercept (x= 0) is y = -2(0) -5 = -5. So one point on the line is (0, -5). The x-intercept (y=0) is 0 = -2x - 5 => 2x = 5 => x = 5/2.
iv. If f(x) = 4x - 3, find f(-1). Use the same technique as (i) above. Thus f(-1) = 4(-1) - 3 = -4-3 = -7.

Answer 2

I think? but i think im rite:)

Answer 3

SO the answer is -7?

Answer 4

yea

Answer 5

but thats not one of my options...

Answer 6

well? im sorry than :I

Answer 7

Wait..are we solving "Given f(x) = X+7/5, solve for f-1(3)."

Answer 8

that's what she said... the question was stated well enough !!

Answer 9

@SolomonZelman Correct but looking at ixerroks first post above, it looks like a completely different question! ..regardless

Answer 10

bubbles are definitely cool, lol !

Answer 11

Well, he is JUST WRONG.

Answer 12

or SHE , who knows ;) ?

Answer 13

lol yeah cx

Answer 14

\[\large y = x + \frac{7}{5}\]

rewrite f^-1(x) means you find the inverse of this function...you do this by switching the x and 'y' variables and then solving again for 'y'

\[\large x = y + \frac{7}{5}\]

To solve for 'y' again...subtract 7/5 from both sides of the equation

\[\large y = x - \frac{7}{5}\]

Now we focus on the fact it asks for f^-1(3) ...we now plug in 3 for every 'x' we see in our equation...

\[\large y = 3 - \frac{7}{5}\]
\[\large y = \frac{15 - 7}{5}\]
\[\large y = \frac{8}{5}\]

Answer 15

Sorry then look like i got the wrong question (oops)

Answer 16

its \[(x+7) / 5\]

Answer 17

Oh. Sorry about that @bubbles-are-cool.

Answer 18

its fine o:

Answer 19

Thanks :) @bubbles-are-cool. I had just got the question mixed up :$

Answer 20

Ahh..changes things lol

\[\large y = \frac{x + 7}{5}\]

Again switch

\[\large x = \frac{y + 7}{5}\]

Multiply both sides by 5

\[\large 5x = y + 7\]

subtract 7 from both sides

\[\large y = 5x - 7\]

NOW plug in x = 3

\[\large y = 5(3) - 7\]
\[\large y = 15 - 7\]
\[\large y = 8\]

Answer 21

lol thanks so much!

Answer 22

No problem :)

Answer 23

hey good job @johnweldon1993