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Need help with a Jacob's Geometry problem


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I suspect that the real problem is with my son who is trying to argue me into an early grave, but here goes.

 

2nd Edition Chapter 3. lesson 6, Set 2, Problem 27.

 

The problem shows a diagram of two perpendicular lines that create 4 right angles. The diagram shows you points on the lines with letter names. Two of the angles are also given number names.

 

Given: Angle 1 and angle 2 are a linear pair and angle 1 = angle 2.

 

Prove: Line SA is perpendicular to line HR.

 

Ds insists that he cannot prove anything about the lines because the given does not include the letters on the diagram. I insist that the diagram is given as well.

 

What do you say? I mean, I think he's arguing himself into a box where of course he can't solve the problem. I need back up.

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The problem shows a diagram of two perpendicular lines that create 4 right angles. The diagram shows you points on the lines with letter names. Two of the angles are also given number names.

 

Given: Angle 1 and angle 2 are a linear pair and angle 1 = angle 2.

 

Prove: Line SA is perpendicular to line HR.

 

Ds insists that he cannot prove anything about the lines because the given does not include the letters on the diagram. I insist that the diagram is given as well.

 

Without seeing the problem, I would suspect the sole purpose of the letters is to label the lines: the line SA, and the line HR. And the problem does mention these letters: "Prove: Line SA is perpendicular to line HR." This is simply describing which lines they are talking about. There is nothing else that has to be "given", since there is a figure.

 

There is really not anything much to prove:

if angle 1 plus angle 2=180 degrees (linear pair, by definition)

and angle 1=angle 2 (given),

then angle 1=angle2=90 degrees - so the lines are perpendicular.

 

Not sure I understand what his problem is.

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Not sure I understand what his problem is.

 

Sounds more like he wants an excuse to not do the problem and/or feels like being argumentative.

 

Kiana wins the prize. That is his problem. Sigh. I found something on the internet that said that the given is given explicitly in the givens or implicitly in the diagram. He wouldn't take my word for it but since it was in black and white from someone else, he would accept it. :banghead:

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What I want to know is how on earth you are in Chapter 3 already? Sigh....well, we did start at least a week after you. Must resist the urge to accelerate, must resist, must resist.....I'm just going to keep repeating it.:D

 

But, thanks for giving me a preview of what I have to look forward to.

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What I want to know is how on earth you are in Chapter 3 already? Sigh....well, we did start at least a week after you. Must resist the urge to accelerate, must resist, must resist.....I'm just going to keep repeating it.:D

 

But, thanks for giving me a preview of what I have to look forward to.

 

LOL - We got a head start at the end of last school year. Don't worry!

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