



 
Hi Jessica. 12 years ago, Theresa would be 20 and Joni would be 16 and since 20 is not twice as old as 16, then your answers aren't right. You can do this with algebra though: Then T = J + 4 (that means Theresa is 4 years older than Joni today) Well, we know T = J + 4, so we can substitute in (J + 4) wherever we see T (that's what equal means!) So (T  12) becomes ( (J+4)  12). And the whole second equation is just ( (J+4)  12) = 2 (J  12). Solve for J and use that to find T.  


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