7149
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2011-02-01T00:00:01
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<p>We define $a\oplus b = ab + a + b $. Given that $3 \oplus 5= 2 \oplus x$, what is the value of $x$?<br></br>
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If you liked this problem, <a href="http://nrich.maths.org/5674&part=">here is an NRICH task</a> which challenges you to use similar mathematical ideas. <br></br>
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$3\oplus 5 = 3\times 5 + 3 +5 = 23$ and $2\oplus x = 2x
+ 2+ x= 3x + 2$.<br></br>
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These are equal, so $3x + 2 = 23$, i.e. $x=7$.<br></br>
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Weekly Problem 2 - 2011
Weekly Problem 2 - 2011
Algebra
Creating expressions/formulae
Algebra
Using symbols