The perimeter of the isosceles triangle shown is 53 cm.
The value of x is
Pick one
Solution
Solution 1
Evaluating the left side of the equation, we get 9210−9124=86. Therefore the right side of the equation, 210−□, must also equal 86. Since 210−124=86, then the value represented by the □ is 124. Solution 2 Since 9210−9124=(9000+210)−(9000+124)=9000−9000+210−124=210−124, then the value represented by the □ is 124.
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