Answer:
A.
Step-by-step explanation:
Take a look at what happens when squaring either of these...

Notice a couple of patterns.
1. The last term has a positive coefficient. That rules out answer choices C and D.
2. The coefficient of the middle term is either
. So what are <em>a</em> and <em>b</em>? <em>a</em> is the square root of the x^2 term and <em>b</em> is the square root of the y^2 term.

The middle coefficient needs to be either +30 or -30. The answer is choice A.
Answer:
I just learned this about a few weeks ago I hope this helps.
Step-by-step explanation:
Since it's cosine you're only looking at Adjacent and the hypotenuse which the adj is 20 and the hyp is 25 so since cosine is adj/hyp you do 20/25 then simplify it to 20/25 divide both by 5 so it's simplified to 4/5.
Then you do Cos-1(4/5)=36.869 which is rounded to the tenth 36.9 but rounded to the hundredth 36.87.
Hope this helps
Answer:xryuvb
Step-by-step explanation:
M < 2 = m < 6...corresponding angles
m < 5 = m < 8....vertical angles are congruent