''y varies jointly as x and z'' and y=12, x=2, and z=5. Find y when x=10 and z=7

Sagot :

Answer:

y=kxz

12=k(2)(5)

12=k(10)

12=10k

[tex] \frac{12}{10} = \frac{10k}{10} [/tex]

[tex] \frac{6}{5} = k[/tex]

[tex]y = \frac{6}{5} xz \: \: \: \: when \: x = 10 \: \\ and \: z = 7 \\ y = \frac{6}{5} (10)(7) \\ y = \frac{6}{5} (70) \\ y = \frac{420}{5} \\ y = 84[/tex]

Therefore, in this case, y is equal to 84 when x=10 and z=7.