In the rhombus ABCD, the angle BAC intersects the side BC and the diagonal BD
In the rhombus ABCD, the angle BAC intersects the side BC and the diagonal BD, respectively, at points M and N, the angle AMC = 120 degrees. find the angle value ANB.
Let the value of the acute angle of the rhombus be X0, the angle BAD = X0, then the angle BAO = X / 2.
The angle AMB and AMC are adjacent angles, the sum of which is 180, then the angle AMB = 180 – 120 = 60.
The sum of the adjacent angles of the rhombus is 180, then the angle ABC = 180 – ABD = 180 – X.
The diagonals of the rhombus are the bisectors of the angles at the vertices of the rhombus, then the angle BAO = BAD / 2 = X / 2.
AM is the bisector of the angle BAC, then the angle BAM = BAO / 2 = (X / 2) / 2 = X / 4.
In triangle ABM, the sum of the outer angles will be. X / 4 + (180 – X) + 60 = 180.
3 * X / 4 = 60.
X = BAD = 60 * 4/3 = 80.
Then the angle ABC = 180 – 80 = 100.
ABO angle = 100/2 = 50.
In triangle ABN, angle ANB = 180 – BAN – ABN = 180 – 20 – 50 = 110.
Answer: Angle ANB is 110.