Answer:
Step-by-step explanation:
log20 = 1.301 (when you see only "log" with no base, it is taken as a base 10)
This basically means:
(This is the log in exponential form)
Since we don't know what 
is equal to, we will say = x
So to solve for = x, you do the same thing. (convert to exponential form)
Now you will notice that both of these equations are equal to 20.
Since 20 = 20,
we can say 
= 
Another way of saying 100, is 
(make the bases the same)
Now we get 
(we get 2x because an exponent to the power of an exponent (
) is the same as 2 * x)
Because you have the same base, you can just ignore the 10s and focus on the exponents. So you get:
2x = 1.301
x = 0.6505
Answer:
43.8°
Step-by-step explanation:
Applying,
Cosine rule,
From the diagram attached,
x² = y²+z²-2yxcos∅.................... Equation 1
where ∅ = ∠YXZ
Given: x = 8.7 m, y = 10.4 m, z = 12.4 m
Substitute these values into equation 1
8.7² = 10.4²+12.4²-[2×10.4×12.4cos∅]
75.69 = (108.16+153.76)-(257.92cos∅)
75.69 = 261.92-257.92cos∅
collect like terms
257.92cos∅ = 261.92-75.69
257.92cos∅ = 186.23
Divide both sides by the coefficient of cos∅
cos∅ = 186.23/257.92
cos∅ = 0.722
Find the cos⁻¹ of both side.
∅ = cos⁻¹(0.7220)
∅ = 43.78°
∅ = 43.8°
S = a * b where a - <span>length and b - width
a = 24
b = 0.75 * a
S = 24 * 24 * 0.75 = 432</span>
Answer: Choice A. sin(A) = cos(B)
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Explanation:
The rule is that sin(A) = cos(B) if and only if A+B = 90.
Note how
- sin(A) = opposite/hypotenuse = BC/AB
- cos(B) = adjacent/hypotenuse = BC/AB
Since both result in the same fraction BC/AB, this helps us see why sin(A) = cos(B). Similarly, we can find that cos(A) = sin(B).
In the diagram below, the angles A and B are complementary, meaning they add to 90 degrees. So this trick only applies to right triangles.
The side lengths can be anything you want, as long as you're dealing with a right triangle.
