Question

No one will help me!!!..Please Help Me!!!! Take the square root of (-5v + 14) and set that equal to v... V=?... In the question it says V is a real number... There is a possibility that there is no solution but I think there is.... PLEASE HELP!!

Answer 1

hey, can you help me?

Answer 2

Well, we can't solve it if we don't know what -5v + 14 or something equal to.

Expression isn't enough, we need equation to solve.

Answer 3

Is there a way to symplify it though?

Answer 4

well, first I am confused with your question, is that question or is it your work you did for question?

Answer 5

that is the question... It says "Solve for , where v is a real number. (If there is more than one answer, answer them both.).. Then the equation is: The square root of (-5v+14) = v

Answer 6

Oh okay, so you have the equation \(\sqrt{-5v+14}=v\). What to do first?

Answer 7

thanks for coming back!

Answer 8

yes

Answer 9

we don't like square root, right? how to get rid of it?

Answer 10

by squaring both sides right?

Answer 11

yes, squaring both sides, we now get \(-5v+14 = v^2\).
Any idea what to do next? this equation look familiar to you that we can solve?

Answer 12

- 14 from both sides next?

Answer 13

hmm, yeah, but do that to -5v too

Answer 14

+5v from both sides

Answer 15

so then, 0=v^2-14+5v?

Answer 16

Right, try to arrange it to like this form 0=ax^2+bx+c

Answer 17

x^2 + 5v + (-14)?

Answer 18

Yes, you can simplify it to 0 = v^2+5v-14. What next?

Answer 19

make it (v+?)+(v+?).... right?

Answer 20

Yeah

Answer 21

or you can use quadratic formula. either way works

Answer 22

what is the quadratic formula?

Answer 23

You just go ahead and factor.

Answer 24

make it into (v+_)(v-_)

Answer 25

the numbers have to add to equal 5 and multiply to equal -14 right?

Answer 26

right

Answer 27

a+b=5, ab=-14

Answer 28

(v+7)+(v-2)=0

Answer 29

now what?

Answer 30

(v+7)(v-2)=0

No + sign in between

Answer 31

ok, but how do we finish solving it?

Answer 32

without going back to the original equation?

Answer 33

So we know that (v+7)(v-2)=0

So that mean either (v+7) have to be 0 or (v-2) =0

So split it into v+7=0 and v-2=0

Answer 34

Now can you solve it?

Answer 35

yeah, the answer is -7 and 2 right?

Answer 36

well, kind of, we are not done though. Now we have to test and verify if v=-7 and v=2 is true or not.

Answer 37

plug them back into the equation for v.... thanks for helping me!!!!

Answer 38

Try to plug in -7 to original equation \(\sqrt{14-5v}=v\). Is it true?

Answer 39

it equals positive 7

Answer 40

Left side equals +7, right. what about right side?

Answer 41

when I plug 7 in for v I get +7 when I plug 2 in for v I get +2

Answer 42

-7 is the left side so they don't match up

Answer 43

are you still here?