Question 477916
<p>M=my age
Y=your age</p>

<p>My age is now four times yours:
{{{M=4Y}}}</p>

<p>But five years ago it was five times yours:
{{{M-5=5(Y-5)}}}</p>


<p>Plug in 4Y for M:
{{{4Y-5=5(Y-5)}}</p>

<p>Distribute the 5 on the right side:
{{{4Y-5=5Y-25}}}</p>

<p>Simplify both sides
{{{20=Y}}}</p>

<p>So "your age" is 20.  "My age" is 80.</p>

If you check it, that works. Five years ago "you" would have been 15 and "my age" would have been 75. 15*5=75