The complete question in the attached figure
we have that
tan a=7/24 a----> III quadrant
cos b=-12/13 b----> II quadrant
sin (a+b)=?
we know that
sin(a + b) = sin(a)cos(b) + cos(a)sin(b<span>)
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step 1
find sin b
sin²b+cos²b=1------> sin²b=1-cos²b----> 1-(144/169)---> 25/169
sin b=5/13------> is positive because b belong to the II quadrant
step 2
Find sin a and cos a
tan a=7/24
tan a=sin a /cos a-------> sin a=tan a*cos a-----> sin a=(7/24)*cos a
sin a=(7/24)*cos a------> sin²a=(49/576)*cos²a-----> equation 1
sin²a=1-cos²a------> equation 2
equals 1 and 2
(49/576)*cos²a=1-cos²a---> cos²a*[1+(49/576)]=1----> cos²a*[625/576]=1
cos²a=576/625------> cos a=-24/25----> is negative because a belong to III quadrant
cos a=-24/25
sin²a=1-cos²a-----> 1-(576/625)----> sin²a=49/625
sin a=-7/25-----> is negative because a belong to III quadrant
step 3
find sin (a+b)
sin(a + b) = sin(a)cos(b) + cos(a)sin(b)
sin a=-7/25
cos a=-24/25
sin b=5/13
cos b=-12/13
so
sin (a+b)=[-7/25]*[-12/13]+[-24/25]*[5/13]----> [84/325]+[-120/325]
sin (a+b)=-36/325
the answer issin (a+b)=-36/325
Answer: The tall cliff is 118.20 feet tall and the short cliff is 70.32 feet tall.
If you draw a picture with 2 cliffs and a river in the middle, you have find 2 right triangles. In each triangle the adjacent side to our known angle is the river of 90 feet. And the unknown side is the opposite leg.
Therefore, we can set up a tangent equation.
From the top of the short cliff to the top of the tall cliff, we can right and solve the following trig equation:
tan(28) = x /90
x = 47.88
From the top of the short cliff to the bottom, we can right and solve the following trip equation.
tan(38) = x/90
x = 70.32
The 70.32 is also the height of the short cliff. And adding the two answers together will give you the height of the tall cliff.
Answer:
6 square units is the answer

Like fractions are fractions with the same <em>denominator</em>. They are not necessary the same value.
Answer:
72. If the second 3cm has some relevance, leave a note and I'll come back and modify my answer.
Step-by-step explanation:
Givens
L = 6 cm
W = 3 cm
H = 2 cm
I don't know what the extra 3 cm is for.
Formula
SA = 2*L*W + 2*L*H + 2*H*W
SA = 2*6*3 + 2*6*2 + 2*2*3
SA = 36 + 24 + 12
SA = 72