Good math, help!! o

Take the midpoint G on BC, connect AG, and cross CE to point F.

Angle 1 = angle 2, derive the angle 1 = angle fbc, and then get the triangle fbc is an isosceles triangle, then ag is the perpendicular line and the angle bisector.

Then according to the characteristics of the rhombus, it can be deduced that the triangle BEF is all equal to the triangle BGF, then the angle BFE + angle EBF = 90 ° = 3 times the angle 1, and then the angle ADC = 60 °, the angle BCD = 120 °, anyway, after some derivation, the triangle DFC is a right triangle with the angle DCF as a right angle, and an angle is 30 °, then the next good thing is to forget it, DF is equal to 4

My idea for this is to try to prove that the angle 1 = 30°, which is very intuitive...

Extend CE, the extension line of the DA is at G; Connect the AF.

Because BG is parallel to BC, angle 1 = angle ega = angle 2. Therefore, the triangle gfd is an isosceles triangle. i.e., fd=fg.

And because, EA=EB, the triangle age and the triangle BCE are congruent.

Therefore, ga=bc=da. So A is the midpoint of Dg, i.e., Fa is perpendicular to Dg.

Let ef=x, then according to the Pythagorean theorem:

eg^2=ag^2-ea^2。That is: eg=3ef 2+ea 2+ag 2=(eg+ef) 2 i.e.: x 2 + square of root number 3 + 2 times the square of root number 3 = (x + 3) 2 Therefore, x = 1 so df = 4

Base attribute*, x is the number of gems.

The increased stat value increases as the number of gems increases.

Attributes after setting 14 gems = base attribute *, the 15th gem increases:

Add Attribute = Base Attribute * Base Attribute *

Because the area of the three-rent old angular abc is 1, so the xy=2 in the point A and because the point A is on y=m x, the disadvantage of the silver rise is m=2 straight line y=x+1

The coordinates of point A are (1,2).

When y=0.

x = -1 and the length of the socks is 3 in BC

Because AB is 2 in length

So the triangle abc area is 3

Solution: If the point p is on the x-axis, then the p coordinate is (0,k).

The slope of the straight line PA is: kpa=[k-(-5)] [0-(-2)]=(k+5) 2

The slope of the straight line pb is: kpb = (k-6) (0-6) = (k-6) (-6) because the angle apb is a right angle.

then kpa*kpb=-1

So [(k+5) 2]*[k-6) (-6)]=-1 is simplified to k 2-k-42=0

i.e. (k-7)(k+6)=0

The solution yields k=7 or k=-6

So the p coordinate is (0,7) or (0,-6).

Similarity: Let p(0,y)b make a perpendicular line to the y-axis.

You can get: 2 (y+5)=(y-6) 6

y=7 or y=-6

（0，7）（0，-6）

You can set the point p (0,y), and according to the operation of the vector, the product of the two perpendicular is 0, I don't know if you have learned it

Let the coordinates of point p be (0,y).

By apb=90°, i.e. ap is perpendicular to bp.

The slope of the straight line AP is y+5 2, the slope of the straight line BP is y-6 -6, AP is perpendicular to BP, and the product of the slope of AP and the slope of BP is -1:;

i.e. y+5 2*y-6 -6=-1;

The solution yields y = 7 or -6

The coordinates of point p are (0,7) (0,-6).

[Note: Prerequisites: The circumferential angle on the diameter is a right angle] Solution:

It is easy to know that the equation for a circle with the diameter of the line segment ab is: x + y -4x-y-42 = 0Let x=0, get y -y-42=0

=>y1=-6,y2=7.From the question design, it can be seen that p(0,-6) or p(0,7)[Solution 2] Solution:

The point p is on the y-axis, so p(0,p) can be set∵apb=90º.===>kap×kbp=-1.

=>[(p+5)/2]×[p-6)/(-6)]=-1.===>(p+5)(p-6)+12=0.===>p²-p-42=0.

=>(p+6)(p-7)=0.===>p1=-6,p2=7.Point p(0,-6), or p(0,7).

There are x cubic meters of wood for tables, and (23-x) square of wood for chairs.

According to the title: you can make 5x tables and 3* (23-x) chairs.

In order to make it exactly matched, the number of chairs should be 4 times the number of tables, i.e. 3*(23-x) 5x=4

Solve the equation to get x=3

Therefore, 3 cubic meters of wood are used to make tables, and 20 cubic meters of wood are used to make chairs, so a total of 15 tables and 60 chairs are made, which just match.

Tables can be made of x-square wood, and chairs can be made of (23-x) square wood.

3（23-x)=20x

69-3x=20x

3x-20x=-69

23x=-69

x=323-3=20 (square) 3x5=15 (sheets) 20x3=60 (sheets) then there are 15 tables and 60 chairs, which are just matched.

1. In the polynomial x -3x + x-1, the number of the highest minor terms is 3 There are 4 terms, which are called cubic quadruals, and the cubic term coefficient is 1, the quadratic term coefficient is -3, the primary term coefficient is 1, and the constant term is -1

2. In the polynomial x -2x+1, the number of the highest minor term is 1 There are 3 terms, which are called two times trinomial, the cubic term coefficient is 0, the quadratic term coefficient is 1, the primary term coefficient is -2, and the constant term is 1

3. The maximum value of algebraic formula 1998-(a-b) is 1998

4. The minimum value of (a+b)-1998 is 1998

5. If| 5x+3 |4x -8xy+3y-9) = 0, then the value of 5(4x -8xy+3y-1) is 40

6. Column algebraic formula.

The sum of squares of three consecutive odd numbers is 8k 3+12k 2-2k-3

The number smaller than 1 2 of the opposite number of m is - 1 2m-3

If n is an integer, then the number represented by n divided by 3 by 1 should be 3n+1

If the length of the rectangle is a, and the width is 2 3, then its circumference is 10a 3

A three-digit ten digit is m, a single digit is 1 smaller than m, and a hundred digit is 3 times m, then this three-digit number is 311m-1

7. In the parentheses to the right of the equal sign, fill in the appropriate items.

2a-b+c-2d=2a+( b+c-2d )

2a-b+c-2d=2a-( b-c+2d )

2a-b+c-2d=( 2a+c )-b+2d )

2a-b+c-2d=( 2a-b )+c-2d )

1. In the polynomial x -3x +x-1, the number of the highest minor term is 3 There are 4 terms, which are called 3 times multinomial, the cubic term coefficient is 1, the quadratic term coefficient is 3, the primary term coefficient is 1, and the constant term is -1