If "y" is inversely proportional to "x" and "y"=15 when "x"=5, What is the value of "y" when "x"=25?

1 Answer
May 3, 2018

y=3y=3

Explanation:

"the initial statement is "yprop1/xthe initial statement is y1x

"to convert to an equation multiply by k the constant"to convert to an equation multiply by k the constant
"of variation"of variation

rArry=kxx1/x=k/xy=k×1x=kx

"to find k use the given condition"to find k use the given condition

y=15" when "x=5y=15 when x=5

y=k/xrArrk=yx=15xx5=75y=kxk=yx=15×5=75

"equation is " color(red)(bar(ul(|color(white)(2/2)color(black)(y=75/x)color(white)(2/2)|)))

"when "x=25" then"

y=75/25=3