From:
Subject: Re: Geometry problems.
Date: 5 Jul 1997 03:52:20 GMT
"George Hibbard III" writes:
> Hello Newsgroup,
>
> I have two geometry problems, which I'm have trouble with and could really
> use a hand.
> Q1. In an isosceles triangle, two angles are equal. The third angle is 20
> degrees more than twice the measure of one of the equal angles. Find the
> angles.
>
> Q2. The first angle of a triangle is twice the measure of the second
> angle. The third angle is 5 degrees less than the first angle. Find the
> measure of the third angle.
>
> I'm really trying to master word problems, but I need that extra helping
> hand. I hope everyone realizes that I'm not trying to just get the answer,
> but more importantly I want to understand how to approach a problem such as
> the aforementioned. I have had a great deal of help from the people of
> this newsgroup, and for that I thank you all very much.
>
> Thanks for the help,
>
> George.
Word problems in math are very difficult...UNTIL...you know how
to solve them...trust me...after seeing what I wrote below, you
will get the idea:
You have an isoceles triangle (two of the angles are equal). In any
triangle...the sum of the interior angles are always 180 degrees...okay
these are just some facts.
Now they said that the 3rd angle is "20 degrees more than twice
the two equal angles"...okay write that down:
1st angle -> x (call it "x" for now...you don't care what the value
is for the moment.
2nd angle -> x
3rd angle -> 2x + 20 (20 degrees more than twice the other...)
okay...we have the facts now...lets solve it knowing that 180
degrees is the sum of the interior angles:
x + x + (2x + 20) = 180.......(1)...equation #1
or,
4x + 20 = 180.......(2)
now, subtract 20 degrees from both sides of the equation
to get:
4x = 160.......(3)
and now divide by 4 on both sides of this equation to get:
x = 40 degrees. We are done right? Nope!
We were asked to get the angles...using this value then:
1st angle -> x = 40 degrees
2nd angle -> x = 40 degrees
3rd angle -> (2x + 20) -> 2(40) + 20 = 80 + 20 = 100 degrees.
That's it...done. Now, the general procedure is the following:
1) Relax...don't freak out...read carefully the problem;
2) collect the facts first...what do we know about the problem;
3) what general facts do we need to know (for example the sum
of the interior angles is always 180 degrees);
4) what is it that they need us to solve.
5) and that is it! Don't make any more of it...alot of people
freak out with math word problems...trust me...do the above and
you will not fail!!! Guaranteed!!!
Vic
For question 2:
(2x) + x + (2x-5) = 180
5x - 5 = 180
5x = 185
x = 37
2x - 5 = 69