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If x^-2-2=-1.96, y^1/3
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12 Sep 2020, 09:58
12 Sep 2020, 09:58
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Question Stats:
77% (01:43) correct
22% (01:42) wrong based on 54 sessions
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If \(x^{-2}-2=-1.96, y^{\frac{1}{3}}-5=-2\), and \(xy>0\), then what is the value of \(xy\) ?
Show: :: OA
135
Re: If x^-2-2=-1.96, y^1/3
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14 Sep 2020, 06:17
14 Sep 2020, 06:17
2
after simplification we will get values of x and y as
x=5,-5
y=27
xy=135 or -135
but given xy>0
so xy=135
x=5,-5
y=27
xy=135 or -135
but given xy>0
so xy=135
If x^-2-2=-1.96, y^1/3
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20 Feb 2021, 09:06
20 Feb 2021, 09:06
1
Solution:
\(x^-^2\)-2=-1.96
\(\frac{1}{x^2}\)=-1.96+2=0.04
\(x^2\)=\(\frac{1}{0.04}\)
\(x^2\)=25
x=5 or -5
\(Y^\frac{1}{3}\)-5=-2
\(Y^\frac{1}{3}\)=3
Cubing both sides
Y=27
As xy>0
x cannot be -5. Thus, x=5
xy=5*27=135
Hope this helps!
\(x^-^2\)-2=-1.96
\(\frac{1}{x^2}\)=-1.96+2=0.04
\(x^2\)=\(\frac{1}{0.04}\)
\(x^2\)=25
x=5 or -5
\(Y^\frac{1}{3}\)-5=-2
\(Y^\frac{1}{3}\)=3
Cubing both sides
Y=27
As xy>0
x cannot be -5. Thus, x=5
xy=5*27=135
Hope this helps!
