Translate the statements into equations. We can use 'x' for dimes and 'y' for quarters.
"<span>A boy has 11 coins in dimes and quarters"

"</span><span>Their value is $1.70"
</span>

<span>
To solve this, we can first solve for one of the variables in the first equation, and then plug that into the second equation:

Subtract 'x' to both sides:

Now plug this value of 'y' into the second equation:
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So this equation could be used to solve the problem.