The old age problem......

x = sister Carol's age now

x + 23 = Charles' age now {Charles is 23 years older than his sister Carol}

x + 16 = Carol's age in 16 years {added 16 onto current age}

x + 39 = Charles' age in 16 years {added 16 onto current age}

x + 39 = 2(x + 16) {in 16 years, he will be twice her age in 16 years}

x + 39 = 2x + 32 {used distributive property}

x = 7 {subtracted x and 32 from each side}

x + 23 = 30 {substituted 7, in for x, into x + 23}

**Charles is 30
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Carol is 7*@AlgebraHouse*
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