Let
x----------> number of weeks
y----------> saved money
we now that
<span>Michael begins with $20 and saves $5 per week
so
y=20+5x------> equation 1
and
</span><span>Lindsey begins with no money, but saves $10 per week
</span><span>y=10x-------> equation 2
</span><span>the number of weeks it will take for Lindsey and Michael to save the same amount of money is when equation 1 is equals to equation 2
</span>
therefore
20+5x=10x------> 10x-5x=20------> 5x=20-----> x=20/5-----> x=4 weeks
the answer is
4 weeks
