stuck in angles !

[marmar29]

hello !
if m�1=3a+40 , m�2=2a+25 and they are complementry angles so a=
A.1
B.2
C.3
D.4
E.5

THE PROBLEM THT THE RIGHT ANSWER IS 4 BUT IT DOESNT WORK OUT WITH ME ??
I JUST WANNA CHECK FRIENDS IS IT 4?? OR THE ANSWER S NOT THERE???

2. THE DISTANCE BETWEEN (-1,2) & ( 3,-4) IS
A.7.2
B.8,2
C.9.2
D.10.2
E.11.2
THANKS

[gmatboost]

3a + 40 + 2a + 25 = 90
[spoiler]5a + 65 = 90[/spoiler]
[spoiler]5a = 25[/spoiler]
[spoiler]a = 5[/spoiler]

(-1,2) & ( 3,-4)
D = sqrt( (x1-x2)^2 + (y1-y2)^2 )
[spoiler]D = sqrt( (-1-3)^2 + (2--4)^2 )[/spoiler]
[spoiler]D = sqrt( (-4)^2 + (6)^2 )[/spoiler]
[spoiler]D = sqrt( 16 + 36 )[/spoiler]
[spoiler]D = sqrt( 52 )[/spoiler]
[spoiler]since sqrt(49) = 7, sqrt(52) is a little bigger than that[/spoiler]