On my test over parallel lines and proportional parts in triangles today, there was a question that asked to solve for x. There was 2 problems with x in them in the triangle. So would I just have to multiply each part by two and set them equal to each other?

can't you see how incomplete your explanation is?

Read that paragraph to anyone not familiar with the diagrams and they will blankly say, "Huh? what triangles?"

To solve for the value of x in a triangle involving parallel lines and proportional parts, you can use the concept of corresponding angles and sides.

Here's a step-by-step explanation of how to approach the problem:

Step 1: Identify the corresponding angles
Look for angles that are in the same position with respect to the parallel lines. These angles are called corresponding angles.

Step 2: Set up a proportion
Using the corresponding angles, set up a proportion involving the sides of the triangle that are opposite those angles. The sides must be on the same line.

For example, let's say we have two parallel lines with a transversal intersecting both lines. In the triangle formed by these lines and the transversal, we have two angles that are corresponding. Let's call them A and A'.

Step 3: Setup the proportion for side lengths
Next, set up a proportion using the side lengths opposite the corresponding angles. In a proportion, you can set the ratios of the corresponding sides equal to each other.

For example:
side A/side A' = side B/side B'

Step 4: Solve the proportion
Now, solve the proportion to find the value of x. Multiply the extreme terms (the first and last) and the means (the middle terms), and then set the two products equal to each other.

For example:
(side A) * (side B') = (side A') * (side B)

This equation will allow you to solve for x.

Step 5: Substitute the values back into the original problem
Once you have found the value of x, you can substitute it back into the original triangle to confirm that the lengths are proportionate.

Remember, it's essential to have well-labeled diagrams and clear identification of corresponding angles and sides in order to solve these types of problems accurately.

By following these steps, you should be able to solve for x in problems involving parallel lines and proportional parts in triangles.