Sutract
-2/8 from 4/5

4/5-(-2/8)= 4/5+2/8 On taking LCM = 42/40= 21/20

Subtract

(negative 2 over 8 −

2

8

) − 4 over 5

4

5

= negative 42 over 40−

42

40

Step 1 of 2: Subtract, sub-step a: Find common denominator.

Find common denominator

negative 2 over 8−

2

8

− 4 over 5

4

5

= −( 2 × 5 ) over ( 8 × 5 )

2 × 5

8 × 5

− ( 4 × 8 ) over ( 5 × 8 )

4 × 8

5 × 8

= negative 10 over 40−

10

40

− 32 over 40

32

40

40 is the least common multiple of denominators 8 and 5. Use it to convert to equivalent fractions with this common denominator.

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.