If 25(5^x) = 1 then x=
A. -2
B. -1
C. 0
D. 1
E. 2
The OA is A.
To solve this PS question should I plug in the values? I'd appreciate some help here. Thanks.
If 25(5^x) = 1 then x=
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Hi gmat_mission.
You can plug in the values or you can solve it algebraically as follows: $$25\left(5^x\right)=1\ \ \Rightarrow\ \ 5^2\cdot5^x=1$$ $$\Rightarrow \ 5^{2+x}=5^0$$ $$\Rightarrow\ \ 2+x=0$$ $$\Rightarrow\ \ x=-2.$$ Hence, the correct answer is the option [spoiler]A=-2[/spoiler].
I hope it helps you.
You can plug in the values or you can solve it algebraically as follows: $$25\left(5^x\right)=1\ \ \Rightarrow\ \ 5^2\cdot5^x=1$$ $$\Rightarrow \ 5^{2+x}=5^0$$ $$\Rightarrow\ \ 2+x=0$$ $$\Rightarrow\ \ x=-2.$$ Hence, the correct answer is the option [spoiler]A=-2[/spoiler].
I hope it helps you.
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Given: (25)(5^x) = 1M7MBA wrote:If 25(5^x) = 1 then x=
A. -2
B. -1
C. 0
D. 1
E. 2
Divide both sides by 25 to get: 5^x = 1/25 (aka 1/5²)
Rewrite 1/25 as 5^(-2) to get: 5^x = 5^(-2)
So, x = -2
Answer: A
Cheers,
Brent
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- Jeff@TargetTestPrep
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(5^2)(5^x) = 5^0M7MBA wrote:If 25(5^x) = 1 then x=
A. -2
B. -1
C. 0
D. 1
E. 2
5^(2 + x) = 5^0
2 + x = 0
x = -2
Alternate Solution:
25(5^x) = 1
5^x = 1/25
5^x = 5^-2
x = -2
Answer: A
Jeffrey Miller
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