Variable y varies directly with variable x, and y = 4 when x = 7.

What is the value of x when y = 12?
I don't know, How can I get the answer?

Question

Variable y varies directly with variable x, and y = 4 when x = 7.  

 

What is the value of x when y = 12?
I don't know, How can I get the answer?

anonymous · Answer

If i am interpretting the problem properly x=y

anonymous · Answer

okay like before y=kx since it is directly varying now put values of y and x to find k which is constant of proportionality 

4=k7
4/7=k

now y=4/7x
12=4/7x
x=21 ans

anonymous · Answer

^

nevermind_justschool · Answer

Thank you so much, do you mind if I write this down for notes?

anonymous · Answer

of course use it in anyway you want.