Answer:
See below.
Step-by-step explanation:

In these types of problems, the first step is to combine like terms. Like terms are terms with the same exponent (power), and the same variable (like all x's). In the above equation, we can combine -5x, 2x and -3y. Let's do it:

The next step would be to factor out the common ratio, which is not applicable here, so your answer would be
-6x + 7y. Hope this helps!
Answer:
0.002
Step-by-step explanation:
Suppose

is the number of possible combinations for a suitcase with a lock consisting of

wheels. If you added one more wheel onto the lock, there would only be 9 allowed possible digits you can use for the new wheel. This means the number of possible combinations for

wheels, or

is given recursively by the formula

starting with

(because you can start the combination with any one of the ten available digits 0 through 9).
For example, if the combination for a 3-wheel lock is 282, then a 4-wheel lock can be any one of 2820, 2821, 2823, ..., 2829 (nine possibilities depending on the second-to-last digit).
By substitution, you have

This means a lock with 55 wheels will have

possible combinations (a number with 53 digits).
Emily is 12, Samantha is 14, and Lauren is 16. Basically all you do to solve this problem is add numbers that are two apart until you find something.
Ex. 2+4+6=12 4+6+8=18 so on and so forth.