Difference between revisions of "1981 AHSME Problems/Problem 1"

(Solution 2)
(Solution 2)
 
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==Solution 1==
 
==Solution 1==
If we square both sides of the <math>\sqrt{x+2} = 2</math>, we will get <math>x+2 = 4</math>, if we square that again, we get <math>(x+2)^2 = \boxed{\textbf{(E) }16}</math>
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Square both sides of the equation to get get <math>x+2 = 4</math>.  Then square both sides again to get <math>(x+2)^2 = \boxed{\textbf{(E) }16}</math>
  
 
==Solution 2==
 
==Solution 2==
We can immediately get that <math>x = 2</math>, after we square <math>(2+2)</math>, we get <math>\boxed{\textbf{(E) }16}</math>
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Solve the equation to find that <math>x = 2</math>. By substituting, we find that <math>(x+2)^2=(2+2)^2=4^2=\boxed{\textbf{(E) }16}</math>
  
 
== See Also ==
 
== See Also ==
{{AHSME box|year=1981|num-b=0|num-a=2}}
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{{AHSME box|year=1981|before=First question|num-a=2}}
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{{MAA Notice}}

Latest revision as of 13:57, 29 June 2025

Problem

If $\sqrt{x+2}=2$, then $(x+2)^2$ equals:

$\textbf{(A)}\ \sqrt{2}\qquad\textbf{(B)}\ 2\qquad\textbf{(C)}\ 4\qquad\textbf{(D)}\ 8\qquad\textbf{(E)}\ 16$


Solution 1

Square both sides of the equation to get get $x+2 = 4$. Then square both sides again to get $(x+2)^2 = \boxed{\textbf{(E) }16}$

Solution 2

Solve the equation to find that $x = 2$. By substituting, we find that $(x+2)^2=(2+2)^2=4^2=\boxed{\textbf{(E) }16}$

See Also

1981 AHSME (ProblemsAnswer KeyResources)
Preceded by
First question
Followed by
Problem 2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
All AHSME Problems and Solutions

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