Middle School Math Problems, Math Problems Middle School ?

From the roof to the edge of the square is high for (3 2+) circles centered on this line.

and the distance to the roof and the two vertices at the bottom of the square is equal.

Let the distance between the center of the circle and the bottom edge of the square be x

x²+(/2)²=r²

3π/2+π-x=r

r²-x²=π²/4

r-x)(r+x)=π²/4

3π/2+π-2x)*(3π/2+π)=π²/4√3π/2+π-2x)=π/(2√3+4)√3π/2+π-2x)=π(4-2√3)/42x=√3π/2+π-3π/2

2x=√3π

x=√3π/2

r=πs=πr²=πππ

Obviously, the center of this circumscribed circle is inside the square and is on the axis of symmetry of this figure.

Let the center of the circle be o, the distance of o from the vertex of the triangle is r, and the distance of o from the top of the square is x, then x+ 3 2* = r

x+√(r^2-(π/2）^2)=π

The solution gives r= so s= r 2= 3

This house has 5 water chestnuts If you have to pass the five water chestnut points, there is no such circumscribed circle... It should be an external circle of 3 points. In that case, the area is cubic of , and since you can't draw a diagram, you want the process, and the process is not easy to say.

The fraction of the same denominator is added and subtracted, the denominator remains unchanged, and the numerator is directly added and subtracted.

The second fraction in the question is preceded by a "-" sign, so it should be -6-(-6)=-6+6=0

The result is bound to be the same as directly substituting the calculation, and it doesn't matter which algorithm you adopt is based entirely on your own ideas and the convenience of the calculation.

However, (x-2) 2 is better than x 2-4x+4 in terms of simplicity and elegance of form, as well as speed and convenience of calculation.

In particular, in this problem, since the new formula y = a(x-2) 2 + 3 is obtained by the displacement transformation, it can be clearly seen at a glance that it is obtained by moving 2 to the right and 3 to the up. If it's all, it's y = ax 2 -4ax +(4a+3), which is not as clear as the dot form.

Because direct substitution is simple, you first square it completely, and then the substitution result is the same, the former is simple.

Set to x4+x)*3+(8-x)*15=60, x=6 when buried, Xiao Wang is bending the cover beam to end the crossing at the 12th minute, so it is up to 5 minutes.

No, how could the traffic police come or three cars?

1。Because it is a one-dimensional equation, the quadratic coefficient of x is 0, so k=1

2.In the same way, the absolute value of k is 0, so k = 1 or -1. However, the one-way coefficient of x cannot be 0, so k cannot be equal to 1. In summary, k = -1.

3。Because it is a one-dimensional equation of x, the coefficient of x is 1. So k-2=4In the same way, K multiplied by K equals 1. So k = 1 or -1.

Points are in need of a lot, thank you!

1. The diagonal of all squares is the diameter of the circle (20cm*2), and the side length of the square is.

Connect the center of the circle and the vertices of the square.

It can be concluded that 20 cm is exactly the radius of a circle.

Make a perpendicular line on one side of the square through the center of the circle.

Make use of the Pythagorean theorem.

It can be calculated that the side length of the square is 20 2cm

Make two perpendicular diameters over a circle, intersect at a, b, c d, four points, and connect four points, and the quadrilateral abcd is this square line, and there should be no problem with the rest.