When the absolute value pa-pb of a (2,0) B (- 1, - 3) P is the largest on the y-axis, the coordinate of point P is

When the absolute value pa-pb of a (2,0) B (- 1, - 3) P is the largest on the y-axis, the coordinate of point P is

A is a (- 2,0) at the symmetry point of Y axis
The point of intersection p between ab line and Y axis is the maximum absolute value pa-pb
Then p (0, - 6)

In the parallelogram ABCD, the diagonal lines AC and BD intersect at the point O, if ∠ BDC = 120 °, ad = 7, BD = 10, calculate the area of the parallelogram ABCD
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In triangle ode, OD = 1 / 2bd = 5, angle DOE = 60 degrees, so OE = 1 / 2od = 5 / 2, de = 5 / 2 √ 3. In triangle ade, let OA = x, then AE = x + 5 / 2, ad = 7, de = 5 / 2 √ 3, there are 7 ^ 2 = (x + 5 / 2) ^ 2 + (5 / 2 √ 3) ^ 2, x = 3. So OA = 3, AC = 6. In triangle ACD, AC = 6, high de = 5

Given the points a (radical 3, - 2), B (- radical 3,4), find the linear AB equation (y = - 3, radical x + 1, right?) if | PA | = | Pb |,
Finding the linear equation of the moving point P

（1)
(points a (- 3, - 2), B (- 3,4)
The slope of AB is k = (4 + 2) / (- 2 √ 3) = - √ 3
According to the point oblique formula, the linear equation is obtained
Y + 2 = - √ 3 (x - √ 3) is y = - √ 3x + 1
You're right
(2)
If | PA | = | Pb |, then the trajectory of point P is the vertical bisector l of line ab
The slope of L is - 1 / KAB = √ 3 / 3
According to the midpoint coordinate formula, the midpoint m coordinate of AB is obtained
xM=(√3-√3)/2=0,yM=(-2+4)/2=1
The equation of the vertical bisector l of AB is
y=√3/3x+1

Diagonal value range of parallelogram
If the perimeter of parallelogram ABCD is 32 and 5ab = 3bC, then the value range of diagonal BD is 0

If ∵ 2 (AB + BC) = 32 ∵ AB + BC = 16 and 5ab = 3bC ∵ AB = 0.6bcab + BC = 0.6bc + BC = 1.6bc = 16 ∵ BC = 10, then AB = 0.6bc = 6ad = BC = 10

Given the point a (- 1,2), B (2, root 7), there is a point P on X continent, so that | PA | = | Pb |, then | PA ||=

You can first draw a rectangular coordinate axis, and then mark two points a and B on the coordinate axis, so that you can clearly see the relationship between them. Connect two points a and B, take the midpoint o, cross the o point to make a vertical line, intersect the X axis to be the P point (the vertical bisector is equivalent to the isosceles triangle three lines in one, so PA = Pb), know the coordinates of o point (0.5,1 + 0.5 * 7 ^ (0.5)), Kop * KAB = - 1, know KAB, find Kop, and calculate Kop, The coordinate of o point is substituted into the linear expression of OP, let y = 0, find x =?, I will not calculate the specific result~

`It is known that the total area of a cone whose generatrix is 3cm is equal to the area of a circle whose radius is 2cm

After the cone is disassembled, it is a sector and a bottom circle. In this problem, the sector area = the area of the circle with a radius of 2cm, so first calculate the area of the circle as 12.56 square centimeter = sector area, and the sector area = 1 / 2 times the generatrix times the arc length. The arc length calculated is the circumference of the bottom circle of the circular cone, and then use the circumference formula of the circle to

Given the points a (0, - 1), B (0,4), point P on the x-axis, PA + Pb = 3 root sign 5, find the coordinates of point P

Let P (x, 0)
|PA | + | Pb | = 3 radical 5
√ [x ^ 2 + (- 1) ^ 2] + √ [x ^ 2 + (4) ^ 2] = 3 radical 5
Transfer to: √ [x ^ 2 + (- 1) ^ 2] =, 3 radical 5 - √ [x ^ 2 + (4) ^ 2]
Square both sides at the same time: x ^ 2 + 1 = 45-6 * radical 5 * √ [x ^ 2 + (4) ^ 2] + x ^ 2 + 16
The result is: root 5 * √ [x ^ 2 + (4) ^ 2] = 10
Square of both sides: 5 * (x ^ 2 + 16) = 100
x^2=4
X = 2 or x = - 2
So p (2,0) or P (- 2,0)

It is known that the total area of a cone whose generatrix is 3cm is equal to the area of a circle whose radius is 2cm. Find the side area of the cone

The side area of the cone = π RL the total area of the cone = π RL + π R2 π is the circumference 3.14 R is the radius of the bottom circle of the cone L is the area of the generatrix long circle of the cone = the total area of the cone = π x R x 3 + π x R x 2 = π x (2x2)

In the plane rectangular coordinate system a (- 1,2) B (2, 7 under the root), find a point P on the X axis, so that lpal = lpbl, and find the value of lpal

Let P (m, 0) l PA L = √ [(m-1) & # 178; + 4] l Pb L = √ [(m-2) & # 178; + 7] ∵ l PA L = l Pb L ∵ [(m-1) & # 178; + 4] = √ [(m-2) & # 178; + 7], i.e. (m-1) & # 178; + 4 = (m-2) & # 178; + 7, i.e. M & # 178; - 2m + 5 = M & # 178; - 4m + 11

It is known that the total area of a cone with generatrix length of 3 is equal to the area of a circle with radius of 2?

The side area of the cone = π RL, the whole area of the cone = π RL + π R2
π is 3.14
R is the radius of the circle at the bottom of the cone
L is the bus length of the cone
Area of circle = total area of cone = π x R x 3 + π x R x 2 = π x (2x2)
4 π = 5 π x R is deduced, and R = 4 / 5 π = 0.8 π
According to the formula, the side area = π x R x 3 = π x 0.8 π x 3 = 2.4 x 3.14