Triangle abc is similar to triangle def. using the image below, prove that lines bc and ef have the same slope. you must show all of your work to receive credit.
triangle abc and def are shown. a is at negative 2, 1. b is at negative 2, 4. c is at 1, 1. d is at 4, 2. e is at 4, 4. f is at 6, 2.

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.

3+x

step-by-step explanation:

question 1: step-by-step explanation:

1/4 of 84 = 84÷4= 21