<PRE><B>Question 62405</B>
If the cost and number of toasters are related by a linear equation then equation will be of the form 
Cost = a number times toasters + another number.

If I use the letter x for the first number and y for the second number then I have two equations using the data in this problem.

Equation 1: 250 000 = 10 000x + y
Equation 2: 350 000 = 20 000x + y

Subtract the first equation from the second equation (which eliminates y from the new equation)
to get
100 000 = 10 000x
Divide both sides of the equation to get x = 10.

Substitute x = 10 into equation 1 and get
250 000 = 10 000 * 10 + y
250 000 = 100 000 + y   Subtract 100 000 from each side of the equation
250 000 - 100 000 = 100 000 - 100 000 + y
150 000 = y 

So the function linking cost in dollars and toaster numbers is
Cost = 10*(Number of toasters) + 150 000
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