Answer:
question 3.3 Answer: Angle 3
question 3.4 Answer: ABD and DBC are complementary angles
question 3.5 Answer: x is 7 degrees (first answer option)
Step-by-step explanation:
First question:
Recall that suplementary angles are those whose addition gives 180 degrees. Therefore the supplementary angle to angle 8 is angle 3.
Second question:
Recall that complementary angles are those angles which added give 90 degrees. Therefore, the only correct answer for this question is the third one: ABD and DBC are complementary angles.
Third question:
Notice that the two angles added should render 90 degrees, therefore, their expression should as well add to 90 degrees. Such can be written in equation form as:
( 6 x - 20 ) + (4 x + 40 ) = 90
combining like terms and later solving for x we get:
6 x + 4 x - 20 + 40 = 90
10 x + 20 = 90
10 x = 90 - 20
10 x = 70
x = 7
Therefore x is 7 degrees
