what is the value of A when r=9 in inverse proportions
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Answer:
3.6 and 2
Step-by-step explanation:
Given R is inversely proportional to A then the equation relating them is
R = [tex]\frac{k}{A}[/tex] ← k is the constant of proportion
To find k use the condition R = 12 when A = 1.5, that is
12 = [tex]\frac{k}{1.5}[/tex] ( multiply both sides by 1.5 )
18 = k
R = [tex]\frac{18}{A}[/tex] ← equation of proportion
(a)
when A = 5, then
R = [tex]\frac{18}{5}[/tex] = 3.6
(b)
when R = 9, then
9 = [tex]\frac{18}{A}[/tex] ( multiply both sides by A )
9A = 18 ( divide both sides by 9 )
A = 2