6m+5n when m =6 and n=4

Step-by-step explanation:First, remove all of the terms from parenthesis. Be careful to handle the signs of each individual term correctly:

5m +5n+6m−4n

Next, group like terms:

5m+6m+5n−4n

Now, combine like terms:

(5+6)m+(5−4)n

11m+1n

11m+n

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.