When added, these two angles are supplementary, meaning that their sum is 180. This means that we can do the following to find x, and eventually DBC:
3x+67+4x+50=180
Simplifies to:
7x+117=180
Then by the Subtraction Prop. of Equality:
7x=63
Then divide by 7 on both sides to get that x=9.
We then substitute 9 into angle DBC.
4(9)+50
=36+50
DBC=86
:)
I want to say 48 bc if 12 is 25 percent then its 1/4 of the students in the class and 12 times 4 is 48
Answer: (4) d=112 (7) 2.75 or 2 3/4
explanation: pictured below
Sum of angles of a triangle = 180°
91 + 10x - 4 + 8x +3 = 180
18x + 90 = 180
18x = 90
x = 5°