Question

What is the value of z so that -9 and 9 are both solutions of x^2 + z = 103 ?

A ) -22

B ) 3

C ) 22

D ) 184

I think the answer is A?

Answer 1

None of these are correct.. No matter what, you're eventually going to end up with a negative and a positive in the equation, and that can't sum up to a positive..

Answer 2

Can you take a picture of the original sheet and show it to me?

Answer 3

Is this from Icademy?

Answer 4

Yes, I believe the answer is either 22 or -22 but I'm not sure which?

Answer 5

Wait I think it's C ) 22! :)

Answer 6

-81+22= -59. That can't be it.

Answer 7

x^2 + 22 = 103
+-22

x^2 = 81
Then you get the square root of 81 which is 9 or -9?

Answer 8

The square root of -9 is -81 though, so it wouldn't be a positive answer like 103. This question is just weird.

Answer 9

In my grade we aren't dealing with negative square roots. Also, -9 x -9 would be 81?
Haha I agree with you on that! I just did the Quick Check and it was 22, though.

Answer 10

For the positive nine, Z would be 22. For the negative nine, Z would be 184

Answer 11

Okay, I was doing it in my head for the square root. Sorry haha.

Answer 12

It's fine. Thank you for the help :)

Answer 13

x^2=103-z
x=sqrt(103-z)
9=sqrt(103-z)
squaring both side
81=103-z
z=103-81=22