1/2 x -2/3 x 9/10 or (-1//3)(9/10) =
write in fraction or rational form not in decimal, don't use decimals and use the fractions provided do not convert to equivalent fractions, and when you are done, simplify you answer, you! + i will mark you as the brainliest answer
do this

98 points djdjsi zisksis sjsjsi sisksj sksjdj sksks sjsisj

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.