If x varies inversely with y and x = 6 when y = 10, how do you find y when x = 8?

1 Answer
Apr 2, 2018

Answer:

Set up an equation # x = 1/y# substitute to find the constant
# x xx y = C# Then substitute again to find the new y

Explanation:

# x =C?y #

# 6 = C/10# multiply both sides by 10

# 6 xx 10 = C/10 xx 10# This gives

# 60 = C. # Now substitute x for 8 in the equation and 60 for C

# 8 = 60/ y # multiply both sides by y

# 8 xx y = 60/y xx y # This gives

# 8y = 60# now divide both sides by 8

# 8y/8 = 60/8# The answer is

# y = 7.5#

As x gets bigger y gets smaller in an inverse relationship.