Other method.
Enter the value of x for each equation and check the equality of the pages of the equation
Can you explain the question in words please?
Given, Jason had an amount of $d in the piggy bank.
After one week, Jason doubled the amount in the piggy bank.
So, after one week the amount in the piggy bank = $
= $(2d)
Another week later, Jason added $20 in the piggy bank.
So after another week, the total amount in the piggy bank = $
Given, that time the piggy bank had $50 in it.
So we can write the equation as,
To find the value of d, we will move 20 to the right side by subtracting it from both sides. We will get,
Now to find d, we will move 2 to the right side by dividing it to both sides. We will get,
We have got the required answer.
The value of d = $15.
<h3>
Answer: 54</h3>
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Explanation:
Focus on the bottom most triangle. The upper angle of this triangle is 360/5 = 72 degrees. This is because the regular pentagon is split into five congruent (aka identical) triangles.
Each of the triangles are isosceles. Let x be the measure of the base angles.
Use the rule that adding the three angles of a triangle gets us 180
angle1+angle2+angle3 = 180
x+x+72 = 180
2x+72 = 180
2x = 180-72
2x = 108
x = 108/2
x = 54 is the answer
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Another way to get the answer:
i = interior angle of a regular polygon with n sides
i = 180(n-2)/n
i = 180(5-2)/5
i = 180(3)/5
i = 540/5
i = 108
Each interior angle of a regular pentagon is 108 degrees.
Angle x marked in blue is half that, so it is 108/2 = 54 degrees
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A third method:
E = exterior angle of a regular polygon with n sides
E = 360/n
E = 360/5
E = 72 degrees is the measure of each exterior angle
i = 180 - E
i = 180-72
i = 108 is the measure of each interior angle.
To wrap things up, we follow the same exact steps at the end of the 2nd section to get 108/2 = 54 as our answer.
Option C is your answer. The way it's worded, it first wants you to find the difference (meaning subtract) between 5 and 6/7 and then multiply by the 5.
