Question

If you people would be so kind as to answering a VERY important question for me.

Z varies jointly with x and y. When x-2 and y-2, z-7
Please help me:/ I will give fan and medal...
@Kristen17

Answer 1

@wolfe8

Answer 2

You mean when x = 2 and y = 2, z = 7, right?
Z varies jointly with x and y means: Z = xyc for some constant c
To figure out c plug in the x,y and z you know.
7 = 2*2*c
you solve for c and get c = 7/4
so the equation is
Z = 7/4 * xy

Answer 3

Idk:/ That's the part that confused me. The paper is a little blurry but I think it has the - instead of an equal sign...

Answer 4

Gotta be =. Makes no sense if it's a minus sign.

Answer 5

Hmm okay. Thank you for looking at it:)

Answer 6

Unless it's saying when x is -2 and y is -2, z is -7.
In that case you get c = - 7/4 and your equation winds up being Z = - 7/4 * xy

Answer 7

Nope. No "is" so guess it is an equal sign. Oh well. Thanks anyways