Current location - Training Enrollment Network - Mathematics courses - On the Middle School Examination Questions of Mathematics in the Senior High School Entrance Examination
On the Middle School Examination Questions of Mathematics in the Senior High School Entrance Examination
If the quadrilateral PEQF is a diamond, PQ is perpendicular to EF, and the intersection point m of PQ and EF is the midpoint of PQ and EF respectively.

According to the meaning of the question

(1) Assuming that point P is in AC and forms a diamond, then

EF= (BC -VL*T)

Tan α =EF/BE, so EF=tan α(BC-VL*T), ME=EF/2.

Then the distance that point P moves on the AC side is: AP=AC-ME, that is, VP*T=6-tan α(BC-VL*T)/2, and t can be obtained.

The main thing is that the moving speed of your line is 43? Or 4.3 or 4/3? Just bring it here and do the math yourself.

(2) Suppose that the point P is on BC, because BC is perpendicular to the straight line L, a diamond cannot be formed.

(3) Assuming that point P is on AB, point P should be on the right side of straight line L. ..

Then: ME still press (1), ME=tan α(BC-VL*T) /2.

At this time, the vertical line of BC is made through point P, and the vertical foot is X, then PX=ME.

Then PX/PB=sin α, so Pb = px/sinα = me/sinα = tan α (BC-VL * t)/2sinα.

And PB=(T-3-4)*5, then calculate: (T-3-4)*5=tan α(BC-VL*T) /2sin α can calculate T.