This is so confusing all of it makes no sense

D).

Step-by-step explanation:

STEP 1a: Find the last angle of the triangle. ( which is angle A)

STEP 1b: Solve the equation for A by adding 90 and 45.

STEP 1c: Then Move all terms not containing A to the right side of the equation by subtracting 135 from both sides of the equation

STEP 1d: Subtract 135 from 180.

STEP 2a: Find side b next.

STEP 2b: The cosine of an angle is equal to the ratio of the adjacent side to the hypotenuse.

STEP 2c: Substitute the name of each side into the definition of the cosine function.

STEP 2d: Set up the equation to solve for the adjacent side, in this case b.

STEP 2e: Substitute the values of each variable into the formula for cosine.

STEP 2f: Cancel the common factor of 2.

HOPE THIS HELPS!

18.75 gallons

step-by-step explanation:

need more detail

step-by-step explanation:

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