Question

Y is inversy proportional to x. When y=7 , x=9 A) work out an equation connecting y and x? B) work out the value of y when x=21

Answer 1

Answer:

see explanation

Step-by-step explanation:

since y is inversely proportional to x the equation relating them is

y = $\frac{k}{x}$ ← k is the constant of proportionality

to find k use the given condition when y = 7, x = 9

k = yx = 7 × 9 = 63

y = $\frac{63}{x}$ ← is the equation connecting them

when x = 21, then

y = $\frac{63}{21}$ = 3