Errors in geometry book?

[maberge]

Page 16 of the geometry guide notes the equation for area of a triangle as (base * height)/2 and the area of a trapezoid as [(base1 + base 2) * height]/2. But in both cases the height should NOT be divided by two, correct? I did not see either of these on the errata page so I thought I would check.

[tim]

Those formulas are correct. Do you have a source for whatever you think the formulas should be instead?

[maberge]

I'm sure there are many different ways to express the formula...I guess my point is that it would be nice for your books and your classes to stick with one format of the formula in the classes and the books and the work shown in the answer key. It may seem minor since the answers will obviously all end up the same but I think it would go a long way towards helping with retention.

[RonPurewal]

Honestly, these are minor differences. If they seem like major differences, that's best taken as an indicator that you should practice your routine algebraic operations a little more"”"”to get to a point where it's effortless to tell that they're the same.

E.g., if (1/2)(bh) and bh/2 look like two different things to you, you should practice routine algebraic operations on fractional expressions until it becomes obvious to you that they're not different.

[RonPurewal]

At this point I'm going to lock this thread, since it doesn't belong in this folder. (Questions about MGMAT books belong in the MGMAT non-CAT folder.)

If there are further questions along the lines of these, please post them there. Thanks.