Difference between revisions of "2022 AMC 8 Problems/Problem 2"

(Created page with "==Problem== Consider these two operations: \begin{align*} a \, \blacklozenge \, b &= a^2 - b^2\\ a \, \bigstar \, b &= (a - b)^2 \end{align*} What is the value of <math>(5 \,...")
 
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Consider these two operations:
 
Consider these two operations:
\begin{align*}
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<cmath>\begin{align*}
 
a \, \blacklozenge \, b &= a^2 - b^2\\
 
a \, \blacklozenge \, b &= a^2 - b^2\\
 
a \, \bigstar \, b &= (a - b)^2
 
a \, \bigstar \, b &= (a - b)^2
\end{align*}
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\end{align*}</cmath>
 
What is the value of <math>(5 \, \blacklozenge \, 3) \, \bigstar \, 6?</math>
 
What is the value of <math>(5 \, \blacklozenge \, 3) \, \bigstar \, 6?</math>
  
 
<math>\textbf{(A) } {-}20\qquad\textbf{(B) } 4\qquad\textbf{(C) } 16\qquad\textbf{(D) } 100\qquad\textbf{(E) } 220</math>
 
<math>\textbf{(A) } {-}20\qquad\textbf{(B) } 4\qquad\textbf{(C) } 16\qquad\textbf{(D) } 100\qquad\textbf{(E) } 220</math>
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==Solution==
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 +
We get that <math>(5 \, \blacklozenge \, 3) = 5^2 - 3^2 = 16</math>, so <cmath>(5 \, \blacklozenge \, 3) \, \bigstar \, 6 = 16 \, \bigstar \, 6 = (16 - 6)^2 = 10^2 = \boxed{\textbf{(D) }100}.</cmath>
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<i>pog</i>
  
 
==See Also==  
 
==See Also==  
 
{{AMC8 box|year=2022|num-b=1|num-a=3}}
 
{{AMC8 box|year=2022|num-b=1|num-a=3}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 10:30, 28 January 2022

Problem

Consider these two operations: \begin{align*} a \, \blacklozenge \, b &= a^2 - b^2\\ a \, \bigstar \, b &= (a - b)^2 \end{align*} What is the value of $(5 \, \blacklozenge \, 3) \, \bigstar \, 6?$

$\textbf{(A) } {-}20\qquad\textbf{(B) } 4\qquad\textbf{(C) } 16\qquad\textbf{(D) } 100\qquad\textbf{(E) } 220$

Solution

We get that $(5 \, \blacklozenge \, 3) = 5^2 - 3^2 = 16$, so \[(5 \, \blacklozenge \, 3) \, \bigstar \, 6 = 16 \, \bigstar \, 6 = (16 - 6)^2 = 10^2 = \boxed{\textbf{(D) }100}.\]

pog

See Also

2022 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
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
All AJHSME/AMC 8 Problems and Solutions

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