The cost to produce $x$ units of wire is $C=45x+450$, while the revenue is $R=70x$. Find all intervals where the product will t least break even.
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Step 1 ：Let's denote the number of units of wire produced and sold as 'x'.

Step 2 ：The total cost of production C(x) is given by the equation $C(x)=45x+450$.

Step 3 ：The revenue function R(x) is given by the equation $R(x)=70x$.

Step 4 ：The break-even point is the point at which total cost equals total revenue, so we need to find the value of 'x' for which $C(x)=R(x)$.

Step 5 ：Setting the two equations equal to each other gives us the equation $45x+450=70x$.

Step 6 ：Subtracting 45x from both sides gives us $450=25x$.

Step 7 ：Dividing both sides by 25 gives us $x=18$.

Step 8 ：Final Answer: The product will at least break even when $x\ge \boxed{{\displaystyle 18}}$.