Someone compiled an ancient question in the Nine Chapters of Arithmetic into the form of a poem, a

Set up bamboo poles x rulers.

x-4)^2+(x-2)^2=x^2

x^2+16-8x+x^2+4-4x=x^2x^2-12x+20=0

x-6)^2=16

x-6=4x=10

Width x 4 = 6 feet.

Length x-2 = 8 feet.

Bamboo pole 10 feet.

Set the bamboo pole x, the door width (x-4), the height (x-2), the Pythagorean theorem:

x-4)^2+(x-2)^2=x^2

x^2-12x+20=0

x=2 (rounded), or x=10

So: the door is 6 feet wide, 8 feet high, and the bamboo pole is 10 feet.

If the rod length is x, the rectangle is wide x-4 and the rectangle is high x-2

By the "diagonal comparison, the oblique rod is just the end of the end. ”

The equation x 2=(x-2) 2+(x-4) 2 is solved to x=10 (the other solution x=2 is not in line with the topic, so it is rounded) The rod is 10 feet long, then the rectangle is 6 feet wide and 8 feet high.

The answer is: 8 feet! Set the bamboo pole has l feet, the rectangular door is a foot long, and the height b feet are more than four feet horizontally

l-a=4;It can be obtained: a=l-4 standing two feet left: l-b=4; Available:

b = l-2 diagonal ratio again, the oblique rod is exactly the end of the end: the square of l = the square of a + the square of b, so the length of l is 8! 6 in height and 4 in length

Pick C Oh, use their daily multiplication, multiply by how many days, it's a total.

The depth of the pool, the length of the reed, the side of the square is half as long.

A right triangle is formed.

If the depth of the pool is x, the length of the reed is x+1

x+1)²=x²+(10/2）²

The solution is x=12

x+1=13

A: The depth of the pool is 12 feet, and the length of the reeds is 13 feet.

Solution: Let the depth of the pool be x feet, which is the length of the reed (x+1) feet, then: the hypotenuse of the right triangle = x+1, a right-angled side is x feet, and the other straight angle edge is: 10 2 = 5 feet, which is obtained by the Pythagorean theorem: (x+1) square = x square + 5 square solution: x=12

A: The pool is 12 feet deep, which is 13 feet long with the reeds.

You sort out your thoughts.

The first is to transport rice, which is empty and full at one time, for a round trip.

Set the full car went for x days, and the empty car went for y days.

x+y=5 (days).

Considering the matter of transporting rice, the distance traveled by the empty car is equal to the distance traveled by the full car 50x=70y

x+y=550x=70y

Finally, use 50x (or 70y) 3 to be the distance between the two places.

Yes, it's a question in the nine chapters of arithmetic.

The distance from the host horse to the guest horse and back is the same, so the time it takes is the same. Yes (3 4-1 3) 2=5 24 (day).So when the guest horse was caught up, it walked 1 3 + 5 24 = 13 24 days, and walked 300 * 13 24 miles, which is the distance traveled by the master horse on 5 24 days.

Therefore, the daily speed of the master horse is (300*13 24) (5 24)=780 (li). It's not hard to understand the questions.

The pool ** is 5 feet away from the edge of the pool, and the reed is 1 foot above the water surface, if the reed length is x, then (x-1)*2+5*2=x*2, calculate to get x=13, then the water depth is 12.

Answer, support me.