Answer:
X=35
Explanation:
Angle M= 60 <-- because we know a triangle=180 and so far we have 40 and 80 in the triangle JKM, 60 degrees is needed to complete 180
The other side of angle M (in the triangle KML)= 120 <-- because we know that a straight edge is 180 degrees and to complete the 180, we need another 120 degrees
so, to find X we need to find how many degrees are needed to complete the 180 degrees of triangle KML
120+25= 145
180-145= 35