Answer:
A.
Step-by-step explanation:
There's a few ways you can go about solving this, but the way I would go with is using sine law.
Sine law:

in the equation above 'A' an angle, and 'a' would be the length of the side opposite to it. Same thing for B.
You are given the angle 90 degrees, and its opposite side length is 2.
You are also given 45 degrees from one of the corners but it doesn't tell you its side length.
There is one corner where it doesn't tell you the angle but you can figure it out using the law that the angles in a triangle must add up to 180 degrees.
So you subtract the other angles to find the angle of the bottom right angle.
180-90-45 = 45
The reason we want to find that angle, is so we can use sin law to find s.
Write down what you have so far:

Now all you need to do is solve for s.

sin 90 is 1.

Now since the answers available are in exact values, you can't just punch this in your calculator.

so,

3xy-5x+9y-45
Step-by-step explanation:
Step by Step Solution
STEP1:STEP2:Pulling out like terms
2.1 Pull out like factors :
3y - 15 = 3 • (y - 5)
Equation at the end of step2: (x • (3y - 5)) + 9 • (y - 5) STEP3:Equation at the end of step 3 x • (3y - 5) + 9 • (y - 5) STEP4:Trying to factor a multi variable polynomial
4.1 Split 3xy-5x+9y-45
4.1 Split 3xy-5x+9y-45
into two 2-term polynomials
-5x+3xy and +9y-45
This partition did not result in a factorization. We'll try another one:
3xy-5x and +9y-45
This partition did not result in a factorization. We'll try another one:
3xy+9y and -5x-45
This partition did not result in a factorization. We'll try another one:
3xy-45 and +9y-5x
This partition did not result in a factorization. We'll try another one:
-45+3xy and +9y-5x
This partition did not result in a factorization. We'll try
X=31
X-23=8
Move the 23 to the right
X=23+8
X=31
Step by step, meaning explaining the equation right and answer?