Right angle trigonometry homework question

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Homework Help Overview

The problem involves a steel plate shaped as one-fourth of a circle with a radius of 60 centimeters, where two holes are to be drilled. The task is to find the coordinates of the centers of these holes, which are positioned at specific angles from the horizontal edge.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the relationship between the radius of the circle and the hypotenuse of the triangles formed. Some attempt to clarify the reasoning behind the 56-centimeter measurement as the hypotenuse in the context of right triangles.

Discussion Status

The discussion is ongoing, with participants exploring the geometric relationships involved. Some guidance has been offered regarding the interpretation of the hypotenuse as a radial measurement, but no consensus has been reached on the specifics of the calculations.

Contextual Notes

There is mention of angles (30° and 60°) and the use of polar coordinates to find rectangular coordinates, which are part of the problem's setup. The original poster expresses confusion about the solution manual's approach, indicating a need for clarification on the triangle configurations.

xxwinexx
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Homework Statement


A steel plate has the form of one-fourth of a circle with a radius of 60 centimeters. Two two-centimeter holes are to be drilled in the plate positioned as shown in the figure. Find the coordinates of the center of each hole.

Homework Equations


I know it's got to be a simple sin/cos right angle equation, but I've no clue how they came about to getting the 56 centimeter measurement to be the hypotenuse on the solution that I have in my manual.

The Attempt at a Solution



I attempted drawing a few right angle triangles that I thought would work, but nothing came from it. If someone could explain how the solution manual was able to get a triangle with 56 as the hypotenuse, I would be able to move forward from there.

I've attached both the image of the problem, and the image of the first part of the solution worked out.
 

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for the first hole you have a 30-60-90 rt triangle with hyp 56 so you should be able to compute the x1 and y1

similarly for the x2 y2
 
It's because it's the radius of the circle. Every hypotenuse along the circumference of a circle that is measured from the centre is going to be the radius of the circle.
 
xxwinexx said:

Homework Statement


A steel plate has the form of one-fourth of a circle with a radius of 60 centimeters. Two two-centimeter holes are to be drilled in the plate positioned as shown in the figure. Find the coordinates of the center of each hole.


Homework Equations


I know it's got to be a simple sin/cos right angle equation, but I've no clue how they came about to getting the 56 centimeter measurement to be the hypotenuse on the solution that I have in my manual.
It looks to me like the two drilled holes are a radial distance of 56 cm from the center, and at angles of 30° and 60° from the horizontal edge.

These values aren't calculated - they're part of the given information in the problem. The positions of the two holes are essentially in polar coordinates, and your job is to find the rectangular coordinates of the holes.
xxwinexx said:

The Attempt at a Solution



I attempted drawing a few right angle triangles that I thought would work, but nothing came from it. If someone could explain how the solution manual was able to get a triangle with 56 as the hypotenuse, I would be able to move forward from there.

I've attached both the image of the problem, and the image of the first part of the solution worked out.
 
jedishrfu said:
for the first hole you have a 30-60-90 rt triangle with hyp 56 so you should be able to compute the x1 and y1

similarly for the x2 y2

Right, that's basically what the solution is saying, I guess I just can't see how they figured that right triangle/hypotenuse out..

Edit: Ohhhh...I wasn't thinking of the 56 as a radial measurement. I feel really dumb now. Thanks guys!
 

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