Question

How to do this ? Medal will be awarded

Answer 1

Using complete sentences, write an indirect proof proving that if x = 40, then 2 over 5x − 7 ≠ 13.

Answer 2

I really need help please

Answer 3

If x = 40 - Then 2 over 5x − 7 ≠ 13 <--- You use 40 and replace It for x In the proof.

Answer 4

2 over 5x − 7 ≠ 13 ----> 2/5(40) ≠ 13 ---> 16 ≠ 13 <---

Answer 5

so step 1is 2/5(40) ≠ 13

Answer 6

To start an indirect proof u will state the opposite of what ur trying to prove

Answer 7

So 5x-7=13

Answer 8

@nikato that is how you start the proof

Answer 9

Oops, it's 2/5x-7

Answer 10

Oh ok

Answer 11

so how does the x=40 fit with this

Answer 12

But u said indirect proof @arilove1d

Answer 13

\[\huge \frac{2} {5x - 7} \ne 13 , ~\text{for}~x = 40\]
\[\huge \frac {2}{5(40) - 7} \ne 13 ~~~~~~ \frac{2}{200-7} \ne 13\]
\[\huge \frac {2}{193} \ne 13 \]

Answer 14

writing in latex without the equation editor is tedious..

Answer 15

In your paragraph write that when you substitute with x = 40, you get 2/193 , which is not equal to 13, therefore .....(blah blah blah and so on)

Answer 16

yeah its an indirect proof . Im sonfused on how you make one i know you start it with t he opposite of what you want to prove

Answer 17

*confused

Answer 18

Ok, so with what I said above. After that when u write in complete sentences how to find x with the opposite equation

Answer 19

Wouldnt it be 2/5(40)-7=13

Answer 20

U should have two different answers. And then say something by contradiction of the given x=40 and the answer u got, therefore 2/5x-7 doesn't equal 13. Something like that I guess

Answer 21

Yea, or u could do what's just did. And said becuz they are not equal, there's a condtradition

Answer 22

Thank you @nikato