ABCD-parallelogram AB = 12 cm АС = 16 cm vertex D is 4 cm away from AC find:
ABCD-parallelogram AB = 12 cm АС = 16 cm vertex D is 4 cm away from AC find: a) S parallelogram b) distance from point D to AB
1. From the vertex D we draw a perpendicular DH to the diagonal AC. Its length is the distance from the top of D to the AC. DH = 4 centimeters.
2. Calculate the area of the triangle ACD:
Area ΔАСD = АС х DH / 2 = 16 х 4/2 = 32 centimeters².
3. According to the properties of a parallelogram, its diagonal divides this geometric figure into 2 equal triangles:
ΔАСD = ΔАВС.
4. Consequently, the area (S) of the parallelogram ABCD = 32 x 2 = 64 centimeters².
5. From the vertex D draw a perpendicular DK to the side of the parallelogram AB. Its length is the distance from the top D to AB.
6. Calculate the length DK using the formula for the area of a parallelogram (S):
S = AB x DK.
DK = S: AB = 64: 12 = 16/3 = 5 1/3 centimeters.
Answer: the area of the parallelogram is 64 centimeters², the distance from the top of D to the side AB is 5 1/3 centimeters.