Answer:

Step-by-step explanation:
Recall the formula for the sine of the double angle:

we know that
, and that
is in the interval between 0 and 90 degrees, where both the functions sine and cosine are non-negative numbers. Based on such, we can find using the Pythagorean trigonometric property that relates sine and cosine of the same angle, what
is:

With this information, we can now complete the value of the sine of the double angle requested:

Answer:
13
Step-by-step explanation:
Answer:
C) QT
Step-by-step explanation:
We must first find the coordinates of C(x,y) which divides AB in the ration m:n=3:2.
We use the formula

and
We plug in the coordinates of A(-5,9) and B(7,-7) and m=3, n=2 to get:
and

C has coordinates
The line segment that contains C is 
See attachment.
Answer:
72cm
Step-by-step explanation:
2 (l + w) = 254
2(55) + 2w = 254
2w = 144
w = 72cm