A random dude is here to save the day!
Step 1: Recall the formula of joint variation, which is
[tex]y = kxz[/tex]
where y varies directly as x and z.
Step 2: Substitute the first given terms. (y is 16, x is 2, and z is 4)
[tex]16 = k(2)(4)[/tex]
Step 3: Multiply and divide both sides by 8.
[tex]16 = k(8)[/tex]
[tex] \frac{16}{8} = \frac{k(8)}{8} [/tex]
[tex]k = 2[/tex]
Step 4: Substitute the next given terms, with k. (x is 1, z is 7, and k is 2.
[tex]y = (2)(1)(7)[/tex]
[tex]y = 14[/tex]
Therefore y is equal to 14 when x is equal to 1 and z is equal to 7.
Hope this helps you!
