Current location - Training Enrollment Network - Mathematics courses - The second volume of the second day of junior high school mathematics examination questions
The second volume of the second day of junior high school mathematics examination questions
The answer is 5.

Your painting is not very standard. Draw it again. Then make two high AE and AF of trapezoid.

It can be seen from the meaning of the question that △BDC is an isosceles right triangle BC = 8, and let DC (= BD) = X.

Then X=4 times the root number 2.

Height AF is not only the height of trapezoid, but also the height of △BDC. From the properties of isosceles right triangle, it can be concluded that △DFC is also an isosceles right triangle FC= half BC=4. If there is Pythagorean theorem, it can be concluded that DF=4.

Because FC=4 EF=AD= 1, so

In the right triangle AEB, be = 3ae = 4, so AB = 5.