How do you solve this math problem?

Question

I can't really understand what to do. The problem states "Find the measurement of angle ABC". I have a picture of it in the link below. If you can tell me how you got it, that would be appreciated. Thanks.

http://s301.photobucket.com/albums/nn53/Shady_Fanatic/?action=view&current=MathHomework.jpg

Answer 1

i think that you have to add (3x + 8) and (x + 4) and make it equal to 180 and then solve for x. then when you do that plug in the answer for x into 3x + 8, and i thnk thats how you get the answer.

Answer 2

Okay.  A line like that is 180 degrees

So you want to solve for X:

3x + 8 + x + 4 = 180

4x + 12 = 180

4x = 168

x = 42

Plug in X in the equation for angle ABC:

3 (42) + 8 = 134 degrees

Answer 3

actually you add like terms

3x+8 + x+4 = 180degrees

3x+x + 8+4 = 180

4x+12 = 180

4x = 180-12

x = 168/4

x = 42

so now plug in x

3x+8

=3*42 + 8

=126+8

=134

ABC = 134 degrees

Answer 4

straight line = 180

so both angles add up to 180

3x + 8 + x + 4 = 180

4x +12 = 180

4x = 168

x = 42

plug 42 for value of x

3x+8

3(42) + 8

126+8

134

Angle ABC = 134 degrees