Use fraction strips to .
2. 3/4 - 1/4 =
3. 5/6 - 1/6=
4. 7/8 - 1/8 =
5. 1 - 2/3=
6. 8/10 - 2/10=
7. 3/4 - 1/4 =
8. 7/6 - 5/6 =

a. is correct

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.