Hi there!
We are given:
cos(7x)cos(4x) = -1 - sin(7x)sin(4x)
Begin by moving all terms with variables to one side:
cos(7x)cos(4x) + sin(7x)sin(4x) = -1
The corresponding trig identity is cos(A - B). Thus:
cos(7x - 4x) = cos(7x)cos(4x) + sin(7x)sin(4x) = -1
cos(3x) = -1
cos = -1 at π, so:
3x = π
x = π/3
We can also find another solution. Let 3π = -1:
3x = 3π
x = π
Thus, solutions on [0, 2π) are π/3 and π.
Answer:
this isn't a specific question you need to be more specific
Step-by-step explanation:
Answer: The measurement of ∠EFG is equal to 70°.
Step-by-step explanation:
Two interior angles who are always opposite to an exterior angle sums to that exterior angle. So we would start as the following:
(6x - 10) + 38 = 7x + 18
In order to find m∠EFG, we must first isolate x. In order to do that, we first add like terms together on both sides.
(6x - 10) + 38 = 7x + 18
6x + 28 = 7x + 18
We then substract 18 on both sides.
6x + 10 = 7x
We finally substract 6x from both sides in order to have the value of x.
x = 10
Now that we know the value of x, we substitute it in our the equation in order to find m∠EFG.
m∠EFG = 6x + 10
m∠EFG = 6(10) + 10
m∠EFG = 60 + 10
m∠EFG = 70
Answer:
64%
Step-by-step explanation:
there are 16 people aged 21 or under out of a total of 25
%
Hope this helps
