It can be seen from the drawing that the subtraction of the two parts is actually the difference between the bottom edge and the waist AB=AC midline BD.
1。 a b+ AD-DC-BC = 13.5- 1 1.5 = 2
AB-BC=2
Again: AB+AD= 13.5
3/2AB= 13.5
AB=9 AB-CB=2 Know BC=7
2:BC+CD = 13.5 AB+AD = 1 1.5 BC-AB = 2
S So: 3/2AB= 1 1.5。
AB=23/3 BC=29/3
2. The known point m (3,4) is on the line segment MN. The line segment MN is translated by 2 units in the negative direction of the X axis and then by 3 units in the positive direction of the Y axis. At this time, the coordinate of the corresponding point M' is (1, 7) _ _ _ _.
3. If the point P(- 1, 2) is known, the coordinates of the point P relative to the X-axis symmetry point P 1 are _(-2, -2)_, and the coordinates of the point P relative to the Y-axis symmetry point P2 are _( 1, 2)_.
4. In triangle ABC, if a (1, 1), b (- 1,-1), and c (2,-1), the area of triangle ABC is _3__.
5. The sum of the external angles of a triangle is 270, and the difference between their two internal angles is 30, so the three internal angles of this triangle are _ 30 _ _ _, 60 and 90 respectively.
The topic should be the sum of two external angles.
6. If the number of diagonals of a polygon is exactly three times the number of sides of the polygon, the sum of the internal angles of the polygon is _ 1250_____.