The new operation X & y = ax + by + C, a, B, C of the definition of rational number XY are the values of 2-7 when 1 & 2 = 9-3 & 3 = 60 & 1 = 2 is known

The new operation X & y = ax + by + C, a, B, C of the definition of rational number XY are the values of 2-7 when 1 & 2 = 9-3 & 3 = 60 & 1 = 2 is known

X & y = ax + by + C, a, B, C are constants
It is known that 1 & 2 = 9 - 3 & 3 = 60 & 1 = 2,
∴{a+2b+c=9,①
{-3a+3b+c=6,②
{b+c=2.③
① * 3 + 2, 9B + 4C = 33. 4
B = 5, C = - 3
Substituting ①, a = 2
∴x&y=2x+5y-3,
2&-7=4-35-3=-34.

Given that the inner angles a, B and C of △ ABC are opposite to a, B and C respectively, and a = 2, B = 3 and CoSb = 45, then the value of sina is______ ．

In ∵ △ ABC, a = 2, B = 3, CoSb = 45, that is SINB = 1 − cos2b = 35. According to the sine theorem Asina = bsinb, Sina = asinbb = 2 × 353 = 25

Given the ABC congruent triangle EFG, the angle B is 68 degrees, and the angle g-angle e is 56 degrees, find the degree of each internal angle of the triangle EFG? Find the writing process,

The triangle ABC is all equal to the triangle EFG, so the angle f = angle B = 68 degrees
Angle G + angle e = 180-68 = 112 degrees,
Angle g-angle e = 56 degrees
The solution is: angle g = 84 degrees, angle e = 28 degrees
So the sum of the internal angles of the triangle EFG is: angle e = 28 degrees, angle f = 68 degrees, angle g = 84 degrees

It is known that △ ABC is all equal to △ EFG, and ∠ B = 68 degrees, ∠ g ― e = 56 degrees

According to the meaning of the title: ∠ a = ∠ e ∠ B = ∠ f ∠ C = ∠ G
∴∠F=68°
∠G － ∠E=56°
∠G +∠E=180°-68°=112°
The solution is ∠ g = 84 °
∠E=28°

In a circle with a radius of 12, the chord length of the vertical bisector radius is___ ．

As shown in the figure, ∵ od = CD = 6, ∵ ad = 63 from Pythagorean theorem, ∵ AB = 123 from vertical diameter theorem, so the answer is: 123

Find the radius of each circle below, C equals 314lmcm

Radius r = C △ 2 π = 314 △ 2 × 3.14 = 50cm

What is the square of a circle with a radius of 12 meters

12x12x3.14 = 452.16 square meters
A: a circle with a radius of 12 meters equals 452.16 square meters
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How to calculate the time difference between two dates in Excel, such as: 2008-6-30 9:56 2008-7-1 7:54, all calculation results are converted to "minutes"
There are two types of dates to deal with. One is the time difference in the same day, the other is the time difference in the same day. For example, 2008-6-30 9:34 and 2008-6-30 10:57 are mixed in the same excel table. How can I calculate the time difference with only one calculation formula? The results are all converted to "minutes"

1. If "2008-6-30 9:34" and "2008-6-30 10:57" are placed in cells A1 and B1 respectively, and C1 is used to calculate the time difference, enter (or copy) the following formula in cell C1:
=(VALUE(B1-A1))*24*60
That is to say, C1 should be set to "normal" or "numerical" format

56.55 out of 70, 33.54 out of 45, the big one, the small one?

For example, the value is 100
4 out of 5 = 80
56 out of 70 = 80
33 out of 55 = 60
45 out of 54 = 83.33333

It is known that in △ ABC, ∠ B = ∠ C, and △ ABC ≌ △ def, if ∠ a + ∠ f = 100 °, the degree of ∠ D can be obtained

Angle d = 20 degree