5 kg to 50 tons, 2 hours to 35 minutes, 2 / 5 square meters to 45 square meters, 0.75 to 1.25, 2 / 3 to 1 / 5

5 kg to 50 tons, 2 hours to 35 minutes, 2 / 5 square meters to 45 square meters, 0.75 to 1.25, 2 / 3 to 1 / 5

5kg to 50t = 5kg: 50000kg = 1 / 2 of 10000 hours to 35 minutes = 120 minutes: 35 minutes = 24 / 7, 2 / 5 square meters to 45 square meters = 40 square meters: 45 square meters = 8 / 9, 0.75 to 1.25 = 0.75 △ 1.25 = 3 / 5, 2 / 3, 1 / 5 = 2 / 3, 1 / 5 = 1 / 5, 1 / 5 = 3

Simple operation: (11-11 / 25 * 7) + (9-11 / 25 * 5) + (7-11 / 25 * 3)

=11 + 9 + 7-11 / 25 (7 + 5 + 3) = 27-33 / 5 = 102 / 5 = 20 (2 / 5) if you have any questions, please ask. Thank you~

As shown in the figure, in △ ABC, ∠ C = 90 °, D, E on BC, BD = de = EC = AC, point out which two triangles in the figure are similar, and prove your conclusion

△AED∽△BEA，… (2 points) it is proved as follows: in △ AED and △ BEA, ∵ ABC, ∵ C = 90 °, BD = de = EC = AC, ∵ AEC is isosceles right triangle, be = BD + de = 2bd = 2Ac, ∵ AEC = 45 °, that is sin ∵ AEC = ACAE, ∵ AE = AC22 = 2Ac, ∵ Aede = beae = 22 = 2 (3 points

Compare the size of A2 + B2 + 1 and a + B + ab

It is proved that the heights of the two waists of an isosceles triangle are equal

ZM: as shown in the figure, in △ BDC and △ CEB, ∵ ∠ DBC = ∠ ECB, ∵ BDC = ∠ CEB = 90 °, BC = BC, ≌ BDC ≌ CEB, CD = be

Given that the function f (x) (x ∈ R) satisfies f (1) = 1 and the derivative f '(x) of F (x) on R is less than 1 / 2, the solution set of the inequality f (lgx) < lgx / 2 + 1 / 2 is

Let f (x) = f (x) - X / 2, because f '(x) < 1 / 2, so f' (x) = f '(x) - (x / 2) < 1 / 2-1 / 2 = 0, that is, f' (x) < 0f (x) = f (x) - X / 2 monotonically decreases on R, f (x) < x / 2 + 1 / 2 is transformed into f (x) = f (x) - X / 2 < 1 / 2 = f (1), then f (lgx) < lgx) / 2 + 1

A room is 6 meters long, 5 meters wide and 4 meters high. The area of doors and windows is 8 square meters. Now we need to paint the four walls and ceiling of the room. How many square meters is the painting area? If 0.4 kg of paint is needed per square meter, how many kg of paint is needed?

6*5+5*4*2+6*4*2-8=
30 + 40 + 48-8 = 110 (M2)
A: the painting area is 110 square meters
0.4 * 110 = 44 (kg)
A: a total of 44 kg of paint is required

If M and N are the two golden section points of line AB, and Mn = a, then ab=

Let AB = x, am / MB = BN / an = (x / 2-A / 2) / (x / 2 + A / 2) = 0.618, that is, (x-a) / (x + a) = 0.618

As shown in the figure, there is a triangle test field. Now we introduce four improved varieties of rice for comparative experiment. We need to divide this test field into four equal areas. Please draw in the figure and explain your division method

Find out the quartering point on the side of triangle BC and connect with A. according to the same base and height, four triangles have the same area

What do am and PM mean and what are they used for?
I only know about time, but I don't know anything else

Am means morning, PM means afternoon
These are Latin abbreviations
Am: ante meridiem (am, Latin for "before noon") morning
PM: post meridiem (PM, Latin for "after noon")