Z varies directly as the square of w, and z = 14 when w = 4. Find z when w = 8?
1 Answer
Mar 9, 2017
Explanation:
#"the square of " w" is "w^2#
#rArrzpropw^2# Convert to an equation by introducing k,
#color(blue)"the constant of variation"#
#rArrz=kw^2#
#"Using "z=14" when "w=4# we can find k
#rArrkxx4^2=14#
#rArrk=14/16=7/8#
#"the equation connecting "z" and "w" is"#
#color(red)(bar(ul(|color(white)(2/2)color(black)(z=7/8w^2)color(white)(2/2)|)))#
#w=8toz=7/cancel(8)^1xxcancel(64)^8=7xx8=56#
