How do you find #y# when #x=10# if #y=8# when #x=20#?

1 Answer
Sep 8, 2017

#y = color(blue)(4)# or #y = color(blue)(16)#

Explanation:

There are 2 possible answers to this.

#k = #constant of variation

For direct variation #y = kx#

#8 = k20#

#k = 0.4#

#y = 0.4(10)#

#y = color(blue)(4)#

For inverse variation #y = k/x^n#

#8 = k/(20)^1#

#k = 160#

#y = 160/(10)^1#

#y = color(blue)(16)#