Ihave been stuck on these two for two days !
1. angleefg and anglegfh are a linear pair, mangleefg=3n+21, and manglegfh=2n+34. what are mangleefg and manglegfh?
2.in the diagram below, mangleacb=68.
find manglebcd.

First of all you should demand your teachers stop teaching you algebra in geometry class.  

1

Linear pairs (and this is the geometry part) are angles that add to 180 degrees, supplementary angles formed by two lines crossing.

3n + 21 + 2n + 34 = 180

5n + 55 = 180

5n = 125

n = 25

mEFG = 3n + 21 = 96 degrees

mCFH = 2n + 34 = 84 degrees

These are indeed supplements, adding to 180 degrees.

2

ACD is a right angle because it makes a linear pair along DF with another right angle.

So

mACB + mBCD = 90 degrees

mBCD = 90 - mACB = 90 - 68

mBCD = 22 degrees

answer: c

because if you look at the chart you can see a pattern and compare it to the question he simplify out your

but i think the formula is f(x)=6x

12cm

the answer is d