# Monthly Archives: August 2017

## Real Solutions (x,y)

How many real solutions are there that satisfy the two equations and ? Source: NCTM Mathematics Teacher, September 2006 Solution The graph of is a circle centered at the origin and radius = . The graph of is a hyperbola … Continue reading

## Twin Liars

Kerry and Kelly are twins. One of them lies on Mondays, Tuesdays, and Wednesdays and tells the truth on the other days of the week. The other lies on Thursdays, Fridays, and Saturdays and tells the truth on the other … Continue reading

Posted in Problem solving
Tagged false, grade 8, logic, NCTM Mathematics Teacher, reasoning, true
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## How Old Are They?

Mary’s and Bob’s ages combined are twice Jane’s age. Mary is years older than Bob. Jane’s age plus Bob’s age is years. How old are they? Source: NCTM Mathematics Teacher, September 2006 Solution Let , and represent the ages of … Continue reading

Posted in Problem solving
Tagged grade 6, NCTM Mathematics Teacher, system of equations
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