List of Cartesian coordinates laws

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When I search online for any list of laws of Cartesian coordinate geometry, I find that it includes quite a few laws such as the law of distance between two points, the law of distance between a point and a line, the law of slope of a straight line and a few additional laws.

But I wanted to find a big list of these laws, after searching with specific words and more deeply I found more laws, but my list is still small, I will include most of what I found in an answer, and I hope my list will be expanded with more laws

It would also be great to have a reference or book with a large number of formulas

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The law of distance between points $A:(x_1,y_1)$ and $B:(x_2,y_2)$

$\bar{AB}=\sqrt{(x_1-x_2 )^2+(y_1-y_2 )^2 }$

Coordinates of the midpoint between points $(x_1,y_1)$ and $(x_2,y_2)$

$M:(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})$

The coordinates of point $C$ that divides (by internal division) the line segment with the ends of $A(x_1,y_1)$ ,$B(x_2,y_2)$ by $\frac{AC}{BC}=\frac{k}{l}$ are:

$C:(\frac{lx_1+kx_2}{k+l},\frac{ly_1+ky_2}{k+l})$

Coordinates of the center of gravity of a triangle with vertices $A:(x_1,y_1)$, $B:(x_2,y_2)$ and $C:(x_3,y_3)$

$O:(\frac{x_1+x_2+x_3}{3},\frac{y_1+y_2+y_3}{3})$

Coordinates of the center of gravity of a group of points $(x_1,y_1),(x_2,y_2),...,(x_n,y_n)$

$O:(\frac{1}{n}\cdot∑_{i=1}^n x_i ,\frac{1}{n}\cdot∑_{i=1}^n y_i )$

The law of slope of a line passing through the points $A:(x_1,y_1)$ and $B:(x_2,y_2)$

$m_{AB}=\frac{y_1-y_2}{x_1-x_2}$

If the slope is zero, the line is parallel to the $xx'$ axis with $y=y_1=y_2=λ$

If the slope is not defined, the line is parallel to the $yy'$ axis with the equation $x=x_1=x_2=λ$

The law of equation of a line with slope m passing through point $(x_0,y_0)$

$y-y_0=m(x-x_0)$

The lines are perpendicular if and only if $m_1×m_2=-1$

The two lines are parallel if and only if $m_1 =m_2$ Miller's Law

The law of slope of a line with equation $ax+by+c=0$ is given as $m=-\frac{a}{b}$

Let $θ$ be the measure of the angle made by the line D with the axis of the separations, which starts from the axis of the separators and calculates counterclockwise, $m_D = tanθ$

$L$ intersects $xx'$ in $(a,0)$, and intersects $yy'$ in $(0,b)$ the equation $L$ is written as:

$\frac{x}{a}+\frac{y}{b}=1$

$L$ is removed from the principle by $P$, and $θ$ is the measure of the angle between P and the axis of the separators, the equation $L$ is written as:

$x\cdot cosθ+y\cdot sinθ-p=0$

The Law of Equation of a Circle Centered at Point $(x_0,y_0)$ and Its Radius $r$

$(x-x_0 )^2+(y-y_0 )^2=r^2$

The law of distance between the point $(x_0,y_0)$ and the line $ax+by+c=0$

$Distance=\frac{|ax_0+by_0+c|}{\sqrt{a^2+b^2}}$

The equation for the point $(x_0,y_0)$ is $(x-x_0)^2+(y-y_0)^2=0$

The law of distance between point $(a,b)$ and line $y=mx+c$

$Distance=\frac{|ma+c-b|}{\sqrt{1+m^2}}$

The law of distance between parallel lines: $y=mx+b_1,y=mx+b_2$

$Distance=\frac{|b_2-b_1|}{\sqrt{1+m^2}}$

The equation of the tangent to a circle $(x-a)^2+(y-b)^2=R^2$ in

Point $(x_0,y_0)$ on the circumference of the circle:

$(x_0-a)⋅(x-a)+(y_0-b)⋅(y-b)=R^2$

The equation of the Mar plane with three points $(x_1,y_1,z_1),(x_2,y_2,z_2),(x_3,y_3,z_3)$

$a(x– x_0 )+b(y– y_0 )+c(z–z_0 )=0$

The general formula for the equation of a plane is from the form ax+by+cz+d=0 The law of distance between points $A:(x_1,y_1,z_1)$ and $B:(x_2,y_2,z_3)$

$\bar{AB}=\sqrt{(x_1-x_2 )^2+(y_1-y_2 )^2+(z_1-z_2 )^2}$

The coordinates of the midpoint between points $(x_1,y_1,z_1)$ and $(x_2,y_2,z_2)$

$M:(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2},\frac{z_1+z_2}{2})$

The law of distance between the point $(x_0,y_0,z_0)$ and the plane $ax+by+cz+d=0$

$Distance=\frac{|ax_0+by_0+cz_0+d|}{\sqrt{a^2+b^2+c^2}}$

Intermediate equations of a line:

$x=x_0+at$

$y=y_0+bt$

$z=z_0+ct$

In parabola $y^2=4px$

The equation of the tangent at point $(x_0,y_0)$ that lies on the parabola

$y\cdot y_0=2p(x+x_0)$

Parabola guide $x=-p$

Parabola focus $F:(p,0)$

Ellipse equation

$\frac{(x-x_0)^2}{a^2} +\frac{(y-y_0)^2}{b^2}=1$

coordinates $O:(x_0,y_0)$ Focal distance from center of ellipsis

c=\sqrt{|a^2-b^2|)}

The length of the large diameter is $2a$ in case of $a>b$ is $2b$ and is equal to in case of $b>a$

Hyperbola equation

$±\frac{(x-x_0 )^2}{a^2}∓\frac{(y-y_0 )^2}{b^2}=1$

coordinates $O:(x_0,y_0)$

Focal distance from the center of the ellipsis

$c=\sqrt{a^2+b^2}$

General equation of a conical section

$Ax^2+Bxy+Cy^2+Dx+Ey+F=0$

The conic segments described in this equation can be classified using the characteristic

$B^2-4AC$

If the cone is not decaying, then The equation represents an ellipse if $B^2-4AC<0$ and if $A=C$ and $B=0$ it is a special case of an ellipse and the equation represents a circle and if $B^2-4AC=0$ the equation represents a parabola and if $B^2-4AC>0$ the equation represents a hyperbola If we also have $A+C=0$, then the equation represents an isosceles hyperbola

In polar coordinates, the equation of a circle with center $(a_0,θ_0)$ and radius $r$ is:

$a^2+(a_0)^2-2a\cdot a_0\cdot cos(θ-θ_0 )=r^2$

The Cartesian equation of a three-point circle $(x_1,y_1,(x_2,y_2),(x_3,y_3)$

$\frac{(x-x_1 )(x-x_2 )+(y-y_1 )(y-y_2 )}{(y-y_1 )(x-x_2 )-(y-y_2 )(x-x_1 ) }=\frac{(x_3-x_1 )(x_3-x_2 )+(y_3-y_1 )(y_3-y_2 )}{(y_3-y_1 )(x_3-x_2 )-(y_3-y_2 )(x_3-x_1) )}$

The bisector equations of the lines $a_1 x+b_1 y+c_1=0$ and $a_2 x+b_2 y+c_2=0$ are:

$\frac{a_1 x+b_1 y+c_1}{\sqrt{(a_1 )^2+(b_1 )^2}}=±\frac{a_2 x+b_2 y+c_2}{\sqrt{(a_2 )^2+(b_2 )^2}}$

The equation of a line segment limited by points (x_1,y_1) and (x_2,y_2) is:

$\sqrt{(x-x_1 )^2+(y-y_1 )^2}+\sqrt{(x-x_2 )^2+(y-y_2 )^2}=\sqrt{(x_1-x_2 )^2+(y_1-y_2 )^2}$

The equation of the line from which the line segment is excluded is limited by the points $(x_1,y_1)$ and $(x_2,y_2)$ is:

$|\sqrt{(x-x_1)^2+(y-y_1)^2}-\sqrt{(x-x_2 )^2+(y-y_2 )^2}|=\sqrt{(x_1-x_2)^2+(y_1-y_2 )^2}$