Answer:

Step-by-step explanation:
In order to find the side mentioned (IJ), we need to use SOH CAH TOA.
SOH CAH TOA is an acronym to help us remember what sin, cos, and tan mean. It stands for:
Sin = Opposite / Hypotenuse
Cosine = Adjacent / Hypotenuse
Tan = Opposite / Adjacent
Since we know the measure of angle K (42) and we know one of the sides, we can use this to find the missing length.
Since the side given to us is the hypotenuse, and we're looking for the side opposite of the angle (IJ), the only possible one to use would be SIN as it includes Opposite and Hypotenuse.
Our equation is now this: 
Let's now solve for x.
Therefore, the length of IJ will be around 2.01.
Hope this helped!
The answer is D or the fourth choice, 12
(AAA) Corresponding angles are congruent.
Therefore, the sides of the triangles are proportional:
cross multiply
use distributive property
subtract 100 from both sides
divide both sides by 100

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(SAS)
If two sides and the included angle of one triangle are equal to the corresponding sides and angle of another triangle, the triangles are congruent.
Therefore we have the equation:

The perimeter of △PQR:

Substitute the value of y to the expression:

C is the answer. By only looking at the domain (the stuff on the right in the functions), you can see that the first equation has a hole at x=2, meaning it does not have a value here at x=2. When x<2, there are values for the 1st function. When x>2, there are values for the second function, as well as when x=2