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The first math problem. Urgent! ! ! !
Solution: (1)① Find the side length of two triangles according to time and speed, and judge the congruence of two triangles according to SAS.

(2) According to the conditions that congruent triangles should meet, explore the relationship between edges, and then according to the formula of distance = speed × time, first find out the moving time of point P, and then find out the moving speed of point Q;

(2) According to the meaning of the question and graphic analysis, it is found that point Q is faster than point P, so if we want to meet for the first time, we should take two sides of an equilateral triangle longer than point P. 。

Solution: solution: (1)①∫t = 1 sec,

∴ BP = CQ = 3× 1 = 3cm,

∫AB = 10cm, and point D is the midpoint of AB.

∴BD=5 cm

∫PC = BC-BP,BC=8 cm,

PC = 8-3 = 5 cm,

∴PC=BD.

AB = AC,

∴∠B=∠C,

∴△BPD≌△CPQ.

②∵vP≠vQ,∴BP≠CQ,

And ∵△BPD?△CPQ, ∠B=∠C, BP=PC=4, CQ=BD=5,

∴ point p, point q moved by t=BP/3=4/3 seconds,

∴VQ = CQ/t = 5/(4/3)= 15/4cm/s;

(2) suppose that point p and point q meet for the first time after x seconds,

From the meaning of the title, it is 15/4x = 3x+2x 10.

The solution is x=80/3 seconds.

∴ The point moved by 80/3×3=80 cm.

∵80═56+24=2×28+24,

Point p and point q meet on the side of AB,

After 80/3 seconds, point P and point Q meet for the first time on the AB side.