Explain how to find an unknown value in a ratio by using a unit rate.

First, we need to define a ratio, the relationship between two measurements or numbers.The first form of a unit rate is made by simply taking one number and placing it over the other, as in division.For example, if you want to express the statement, There are 24 eggs in 2 dozens of eggs.in fraction form it would be 24/2.The second form is to use the phrase, “is to”, between the things you are comparing, to denote that they are a ratio. If you take the example using this form, the answer would be, “24 is to 2”.The third form is to use a colon to between the numbers that we are comparing; this is the standard ratio form.A rate is a special ratio that is composed of two different units or things; think of it as a ratio with words.It's like describing what things are equal to in the simplest and most convenient form. That should help! 

1. isolate the variable, in this case, d. subtract 35.5 on both sides of the equation.2. 52 subtracted by 35.5 is 16.53. therefore your answer would be d= 16.5this is the basics of pre algebra, isolating variable through adding, subtracting, multiplying, and dividing, if you have any other questions to ask just comment!