Let S = {0, 1} and consider the partial order relation R defined on S ✕ S as follows: For all ordered pairs (a, b) and (c, d) in S ✕ S, (a, b) R (c, d) ⇔ a ≤ c and b ≤ d, where ≤ denotes the usual "less than or equal to" relation for real numbers. Find a chain of length 2 for R.

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.

493 would be the correct answer

step-by-step explanation: