485, because the mean means you need to calculate the average. to find the average, you take the smallest number from the data set and the largest number. add the largest number by the smallest number and divide by the set of numbers you added (2). Example: (720+250=970 divided by 2 =485)
just like the previous one, we sum the sides to get the perimeter.

Answer:
√10 / 10
Step-by-step explanation:
tan θ > 0 and sin θ < 0, so θ is in quadrant III. That means cos θ < 0.
cos(θ + π/4)
Use angle sum formula.
cos θ cos(π/4) − sin θ sin(π/4)
½√2 cos θ − ½√2 sin θ
Factor.
½√2 cos θ (1 − tan θ)
½√2 cos θ (1 − 2)
-½√2 cos θ
Write in terms of secant.
-½√2 / sec θ
Use Pythagorean identity (remember that cos θ < 0).
-½√2 / -√(1 + tan²θ)
-½√2 / -√(1 + 2²)
½√2 / √5
√10 / 10
We have the formula (sin x)^2 + (cos x)^2 = 1;
Then, sin α =

cos β =

We apply the formula sin ( α + β ) = sin α x cos β + sin β x cos α = (3/5)x(4/5) + (4/5)x(3/5) = 12/25 + 12/25 = 24/25;