Variation math question?
if y varies inversely varies as x y=5 x=2 find y when x=20
if y varies inversely varies as x y=5 x=2 find y when x=20
Iggy Rocko
y = k/x for some k
5 = k/2
k = 10
y = 10/20 = 1/2
Wayne DeguMan
y ∝ 1/x
so, y = k/x
Then, 5 = k/2
Hence, k = 10
Therefore, y = 10/x
With x = 20, we have y = 10/20 = 1/2
:)>
Krishnamurthy
If y varies inversely with x, it means y = k/x or xy = k.
If y varies inversely as x y = 5 x = 2
find y when x = 20
?
Rule
if y varies inversely varies as x
then
y = k/x , with constant k≠0
?
> y varies inversely varies as x
TRANSLATION: y = (1/k) x.............[1]
// First, solve for k
When y = 5, x = 2 ⇒
..........5 = (1/k)(2)
..........5k = 2
..........k = 2/5
So equation is y = (1/(2/5)) x ⇒
..............................y = (5/2) x
When x = 20, y = (5/2)(20) ⇒
......................y = 50..........................ANS