<PRE><B>Question 1208698</B>
&lt;br&gt;
To help you overcome your frustration in setting up equations correctly, it should help to remember that, when things are being combined in an equation using addition or subtraction, the things must be the same kinds of things.&lt;br&gt;
Your equation in this example is&lt;br&gt;
x-0.15=425,000&lt;br&gt;
You have defined x to be the original cost of the model; and 425,000 is the reduced price of the model.  So those two things in your equation are the same kinds of things -- they are both prices, or, more generally, amounts of money.&lt;br&gt;
But the 0.15 in your equation is a percentage - it is not an amount of money.&lt;br&gt;
When you are learning to set up equations for solving problem, it might help to be more detailed in what you write -- maybe like this:&lt;br&gt;
original price: x
amount of price reduction: 0.15x (&quot;0.15x&quot; is an amount of money; &quot;0.15&quot; is not)
reduced price: x - 0.15x
reduced price: 425,000&lt;br&gt;
Now you have two expressions for the reduced price.  Set those two expressions equal to each other to get the equation you need:&lt;br&gt;
x - 0.15x = 425,000&lt;br&gt;
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