Which of these angles are supplementary? a. 100o and 90o b. 78o and 102o c. 54o and 146o d. 12o and 78o

B. 78 degrees and 102 degrees

B

Step-by-step explanation:

Supplementary angles add to 180 degrees. Add each of the angles to see if they add to 180.

A. 100 + 90 = 190 NO

B. 78 + 102 = 180 YES

C. 54 + 146 = 200 NO

D. 12 + 78 = 90 NO

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x

1/3 + 1/3 ≠ 2/6 because 1/3 alone = 2/6  

step by step explanation:

1/3 + 1/3 = 2/3       2/3=4/6