Answer:
1 = 39 degrees (some theorem, like triangles sharing a bisector or something sorry)
3 = 51 degrees (if 1=39 and 2=90 degrees since its on a right angle, and a triangle's angles add up to 180, then you subtract 1 and 2 from 180 and get 51
Im pretty sure D bonded pair of electrons is the answer
Given:


To find:
The obtuse angle between the given pair of straight lines.
Solution:
The slope intercept form of a line is
...(i)
where, m is slope and b is y-intercept.
The given equations are


On comparing these equations with (i), we get


Angle between two lines whose slopes are
is

Putting
and
, we get



Now,
and 
and 
and 
, so it is an obtuse angle and
, so it is an acute angle.
Therefore, the obtuse angle between the given pair of straight lines is 120°.