Answer:
∠ABD = 45°
Step-by-step explanation:
Since ABCD is a square, its diagonals (Line BD) bisect the angles of the corners of the square (∠ABC) into two equal angles (∠ABD and ∠CBD). The angle of each corner is 90° so you can find ∠ABD.
2(∠ABD) = 90°
∠ABD = 90° ÷ 2
∠ABD = 45°
