Let's label this triangle as triangle ABC. Side AB is 18, side BC is 20 and side CA is 25 and the angle we are looking for is angle C. Use the Law of Cosines to find the missing angle. You have to use the Law of Cosines because in order to use the Law of Sines you have to have an angle given and we don't so we have no other options. In our case,

$c^2=a^2+b^2-2abcosC$ which for us looks like this:

$18^2=20^2+25^2-2(20)(25)cosC$ and

$324=400+625-1000cosC$ and

$324=1025-1000cosC$ and

$-701=-1000cosC$ and

$.701=cosC$

Use the 2nd button and the cos button to find the missing angle.

Angle C = 45.4 which is, rounded to the nearest degree, 45°

8 0

3 years ago

Write a recursive formula for an, the nth term of the sequence 3, -4, -11

yKpoI14uk [10]

Answer:

, 12, 48, 192...

a. Write a recursive formula for the nth term of the sequence

Ans: a(n+1) = 4*a(n)

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b. Write a general formula for the nth term of the sequence

a(n) = 3*4^(n-1)

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c. Calculate S10 for this sequence

Geometric sequence with a(1) = 3 and r = 4

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Step-by-step explanation:

8 0

3 years ago

So i am dealing with equations with triangles, complimentary and supplementary, so what is 42 square + x = 180, so what is the n

Genrish500 [490]

-1584.
multiply 42 times 42 the subtract that from 180

5 0

3 years ago

I had 3 dollars,my mom gave me10 my dad gave me 30 my aunt and uncle gave me 100,i had another 7,how much did i have?

alisha [4.7K]

Answer:

150

Step-by-step explanation:

If you had 3 dollars plus the 10 your mom gave you would have 13. Then, if you dad gave you 30 that would be 43. Plus the 100 your aunt and uncle gave you would be 143. Plus 7 would be your answer of 150

6 0

2 years ago