2-1 reversed is turning it around : 1-2 which equals -1 because there is one left over. B is your answer and hoped I helped!
Given: lines l and m are parallel, and line t is a transversal.
angle pair result/justification
1 and 2 are equal (vertical angles)
6 and 8 are equal (corresponding angles)
1 and 4 are equal (alternate exterior angles)
4 and 8 are supplementary angles (i.e. add up to 180 degrees, a straight angle)
Note:
alternate angles are on opposite sides of the transversal, and each attached to a different (parallel) line.
If they are both enclosed by the parallel lines, they are alternate interior angles (examples: angles 2 and 3, 6 and 7)
If they are both outside of the two parallel lines, they are alternate exterior angles (examples: angles 1 and 4, 5 and 8)
Add 1/6 teaspoon and 1/8 teaspoon. The LCD here is 24, so we're adding
4/24 to 3/24, obtaining 7/24 (teaspoon of pepper, total).
Check the picture below.
the volume of a rectangular prism is just the product of its 3 dimensions, so the volume of those two there is 4*9*6 and 3*6*5.
so the volume for the composite figure is just the sum of those two products.