Step-by-step explanation:
Given : A triangle with side lengths 
To find : Prove that when x > 1, it is a right triangle. Use the Pythagorean theorem and the given side lengths to create an equation. Use the equation to show that this triangle follows the rule describing right triangles. Explain your steps ?
Solution :
For right triangle the Pythagorean theorem is to be satisfied.
i.e. 
Here, 
Substitute the values,



LHS=RHS
It is a right triangle.
This question is about compound interest, but since the interest is such a small number you can use what you know about simple interest to eliminate some answers.
You can immediately eliminate choice A as a clunker, since it is less than the original amount in the account.
Consider what the amount of interest would be if you make the rate much larger than the original rate, say 10%, or 0.1:
$6,500 × 0.1 = $650
If this amount were added to the original amount each year for two years, the total would be:
$6,500 + $650 + $650 = $6,500 + $1,300 = $7,800
This is an over-estimate for the information given, and since choices C and D are even greater than this over-estimate, they can be eliminated. That means choice B is the correct answer.
Answer in fraction form: x = 55/4
Answer in decimal form: x = 13.75
Both forms are equivalent, but they say it in a slightly different way.
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Work Shown:
AC/QY = CD/YW
(x+5)/15 = 5/4
4(x+5) = 15*5
4x+20 = 75
4x = 75-20
4x = 55
x = 55/4
x = 13.75
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Explanations:
- The first step is possible because the polygons are similar. Similar figures have their corresponding sides be in the same proportion or ratio. Note how side AC has the double red angle (at point A) and a single red angle (point C). The side QY has the same idea in the same order. This is why AC corresponds to QY. The ratio AC/QY is the same as CD/YW.
- In the second step, I plugged in the expressions that the diagram shows. This is the substitution property.
- On step 3, I cross multiplied. The general format is A/B = C/D cross multiplies to A*D = B*C.
1.) Find the area of the circle at the top ( A= pi x radius squared )
2.) radius is 5.55 (half of 11.1)
3.) A= pi x 5.55 squared
4.) area of circle =96.77
5.) multiply area of circle(96.77) by height (20)
6.) answer = 1935.38