Multiply the equation:
The solution set is the same, because multiplying both sides of an equation by a non-zero number doesn't change the solution set. In fact, if you rewrite the equation as
Multiplying this by 3 (or whatever number, for all it matters) gives
Now, a product is zero if and only if at least one of the factor is zero. So, either 
or
Since the first is clearly impossible, the second one must be true, which is the original equation.
Problem 10
<h3>Answer: approximately 57.39159 km</h3>
Explanation: You'll use the equation cos(28) = d/65 to solve for d to get d = 65*cos(28) = 57.39159 approximately. We use the cosine ratio because it ties together the adjacent and hypotenuse.
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Problem 11
<h3>Answer: approximately 10.46162 meters </h3>
Explanation: This time we use the sine rule. We have the height as the opposite side (which is unknown, call it x) and the hypotenuse is the ladders length (11). So we have sin(72) = x/11 which solves to x = 11*sin(72) = 10.46162
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Problem 12
<h3>Answer: approximately 16.05724 cm</h3>
Explanation: Now we use the tangent rule to connect the opposite and adjacent sides.
tan(37) = 12.1/x
x*tan(37) = 12.1
x = 12.1/tan(37)
x = 16.05724 approximately
Answer: 
<u>Step-by-step explanation:</u>
a₁, 375, a₃, a₄, 81
First, let's find the ratio (r). There are three multiple from 375 to 81.
![375r^3=81\\\\r^3=\dfrac{81}{375}\\\\\\r^3=\dfrac{27}{125}\qquad \leftarrow simplied\\\\\\\sqrt[3]{r^3} =\sqrt[3]{\dfrac{27}{125}}\\ \\\\r=\dfrac{3}{5}](https://tex.z-dn.net/?f=375r%5E3%3D81%5C%5C%5C%5Cr%5E3%3D%5Cdfrac%7B81%7D%7B375%7D%5C%5C%5C%5C%5C%5Cr%5E3%3D%5Cdfrac%7B27%7D%7B125%7D%5Cqquad%20%5Cleftarrow%20simplied%5C%5C%5C%5C%5C%5C%5Csqrt%5B3%5D%7Br%5E3%7D%20%3D%5Csqrt%5B3%5D%7B%5Cdfrac%7B27%7D%7B125%7D%7D%5C%5C%20%5C%5C%5C%5Cr%3D%5Cdfrac%7B3%7D%7B5%7D)
Next, let's find a₁
Lastly, Use the Infinite Geometric Sum Formula to find the sum:
Answer:
-1
Step-by-step explanation:
4-3/1-2=slope
1/-1
-1
