Coordinate Geometry

If $\mathrm{A}(4,2), \mathrm{B}(6,5)$ and $\mathrm{C}(1,4)$ be the vertices of $\triangle \mathrm{ABC}$ and $\mathrm{AD}$ is a median, then the coordinates of $\mathrm{D}$ are (a) $\left(\frac{5}{2}, 3\right)$ (b) $\left(5, \frac{7}{2}\right)$ (c) $\left(\frac{7}{2}, \frac{9}{2}\right)$ (d) none of these

The correct option is option (c) $\left(\frac{7}{2}, \frac{9}{2}\right)$ $\mathrm{D}$ is the midpoint of BC =>  the coordinates of $\mathrm{D}$ are $ \begin{aligned}...

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If the coordinates of one end of a diameter of a circle are $(2,3)$ and the coordinates of its centre are $(-2,5)$, then the coordinates of the other end of the diameter are (a) $(-6,7)$ (b) $(6 .-7)$ (c) $(4,2)$ (d) $(5,3)$

The correct option is option (a) $(-6,7)$ Let $(\mathrm{x}, \mathrm{y})$ be the coordinates of the other end of the diameter. $-2=\frac{2+x}{2} \Rightarrow x=-6$ $5=\frac{3+y}{2} \Rightarrow...

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The area of $\triangle \mathrm{ABC}$ with vertices $\mathrm{A}(\mathrm{a}, 0), \mathrm{O}(0,0)$ and $\mathrm{B}(0, \mathrm{~b})$ in square units is (a) $a b$ (b) $\frac{1}{2} a b$ (c) $\frac{1}{2} a^{2} b^{2}$ (d) $\frac{1}{2} b^{2}$

The correct option is option (b) $\frac{1}{2} a b$ Let $A\left(x_{1}=a, y_{1}=0\right), 0\left(x_{2}=0, y_{2}=0\right)$ and $B\left(x_{3}=0, y_{3}=b\right)$ be the given vertices. So $...

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If $\mathrm{A}(1,3) \mathrm{B}(-1,2) \mathrm{C}(2,5)$ and $\mathrm{D}(\mathrm{x}, 4)$ are the vertices of a $\| \mathrm{gm} \mathrm{A} \mathrm{BCD}$ then the value of $\mathrm{x}$ is (a) 3 (b) 4 (c) 0 (d) $\frac{3}{2}$

The correct option is option (b) 4 The diagonals of a parallelogram bisect each other. The vertices of the $11 \mathrm{gm} \mathrm{ABCD}$ are $\mathrm{A}(1,3), \mathrm{B}(-1,2) \text { and } C(2,5)...

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$\mathrm{A}(7,-3), \mathrm{B}(5,3)$ and $\mathrm{C}(3,-1)$ are the vertices of a $\triangle \mathrm{ABC}$ and $\mathrm{AD}$ is its median. Prove that the median AD divides $\triangle \mathrm{ABC}$ into two triangles of equal areas.

The vertices of the triangle are $A(7,-3), B(5,3), C(3,-1)$ Coordinates of $D=\left(\frac{5+3}{2}, \frac{3-1}{2}\right)=(4,1)$ For the area of the triangle ADC, let $\mathrm{A}\left(\mathrm{x}_{1},...

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$\mathrm{ABCD}$ is rectangle formed by the points $\mathrm{A}(-1,-1), \mathrm{B}(-1,4), \mathrm{C}(5,4)$ and $\mathrm{D}(5,-1)$. If $\mathrm{P}, \mathrm{Q}, \mathrm{R}$ and $S$ be the midpoints of AB, BC, CD and DA respectively, Show that PQRS is a rhombus.

Since, the points $\mathrm{P}, \mathrm{Q}, \mathrm{R}$ and $\mathrm{S}$ are the midpoint of $\mathrm{AB}, \mathrm{BC}, \mathrm{CD}$ and $\mathrm{DA}$ respectively. Then Coordinates of...

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The base $\mathrm{BC}$ of an equilateral triangle $\mathrm{ABC}$ lies on y-axis. The coordinates of point $\mathrm{C}$ are $(0,-3)$. The origin is the midpoint of the base. Find the coordinates of the points $\mathrm{A}$ and $\mathrm{B}$. Also, find the coordinates of another point $\mathrm{D}$ such that $\mathrm{ABCD}$ is a rhombus.

Let $(0, y)$ be the coordinates of $B$. Then $0=\frac{-3+y}{2} \Rightarrow y=3$ => the coordinates of $\mathrm{B}$ are $(0,3)$ Since,  $A B=B C=A C$ and by symmetry the coordinates of $A$ lies on...

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The line segment joining the points $\mathrm{A}(3,-4)$ and $\mathrm{B}(1,2)$ is trisected at the points $\mathrm{P}(\mathrm{p},-2)$ and $$ Q\left(\frac{5}{3}, q\right) \text {. Find the values of } p \text { and } q \text {. } $$

Let $P$ and $Q$ be the points of trisection of $A B$. => P divides $A B$ in the radio $1: 2$ So, the coordinates of $P$ are $$ \begin{aligned} &x=\frac{\left(m x_{2}+n x_{1}\right)}{(m+n)},...

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Point A lies on the line segment PQ joining $\mathrm{P}(6,-6)$ and $\mathrm{Q}(-4,-1)$ in such a way that $\frac{\mathrm{PA}}{\mathrm{PQ}}=\frac{2}{5} .$ If that point $\mathrm{A}$ also lies on the line $3 \mathrm{x}+\mathrm{k}(\mathrm{y}+1)=0$, find the value of $\mathrm{k}$.

Let the coordinates of $A$ be $(x, y)$. Here $\frac{P A}{P Q}=\frac{2}{5} .$ So, $\mathrm{PA}+\mathrm{AQ}=\mathrm{PQ}$ $\Rightarrow \mathrm{PA}+\mathrm{AQ}=\frac{5 \mathrm{PA}}{2}...

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If the coordinates of points $\mathrm{A}$ and $\mathrm{B}$ are $(-2,-2)$ and $(2,-4)$ respectively. Find the coordinates of the point $\mathrm{P}$ such that $\mathrm{AP}=\frac{3}{7} \mathrm{AB}$, where $\mathrm{P}$ lies on the segment $\mathrm{AB}$.

The coordinates of the points $\mathrm{A}$ and Bare $(-2,-2)$ and $(2,-4)$ respectively, where $\mathrm{AP}=\frac{3}{7} \mathrm{AB}$ and $\mathrm{P}$ lies on the line segment $\mathrm{AB}$. So...

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