Solution: Let's draw a figure of a square with the two opposite vertices (-1, 2) and (3, 2), Let ABCD be a square having known vertices A (- 1, 2) and C (3, 2) respectively. Let B(x₁, y₁) and D(x₂, y₂) be the two unknown vertex We know that the sides of a square are equal to each other. Therefore, AB = BC By Using Distance formula on AB = AC with A (- 1, 2), B(x₁, y₁) and C (3, 2) √ [(x₁ - (-1))2 + (y₁ - 2)2] = √ [(x₁ - 3)2 + (y₁ - 2)2] x₁2 + 2x₁ + 1 + y₁2 - 4y₁ + 4 = x₁2 + 9 - 6x₁ + y₁2 + 4 - 4y₁ (By Simplifying & Transposing) 8x₁ = 8 x₁ = 1 We know that in a square, all interior angles are 90 degrees. In ΔABC AB2 + BC2 = AC2 [By Pythagoras theorem] The distance formula is used to find the distance between AB, BC, and AC (x₁ - (-1))2 + (y₁ - 2)2 + (x₁ - 3)2 + (y₁ - 2)2 = [3 - (-1)]2 + [ 2 - 2 ]2 By using x₁ = 1, (1 + 1)2 + (y₁ - 2)2 + (1 - 3)2 + (y₁ - 2)2 = 16 4 + y₁2 + 4 - 4y₁ + 4 + y₁2 - 4y₁ + 4 = 16 2y₁2 + 16 - 8y₁ = 16 2y₁2 - 8y₁ = 0 y₁ (y₁ - 4) = 0 y₁ = 0 or 4 Now, we have got the coordinates of point B(1, 0) Let's plot the square on a graph as shown below: We see that the vertex opposite to (1, 0) is (1, 4) Hence, for point D we have the coordinates x₂ = 1, y₂ = 4 Hence the required vertices are B (1, 0) and D (1, 4). ☛ Check: NCERT Solutions Class 10 Maths Chapter 7 Video Solution: The two opposite vertices of a square are (-1, 2) and (3, 2). Find the coordinates of the other two vertices.Maths NCERT Solutions Class 10 Chapter 7 Exercise 7.4 Question 4 Summary: The two opposite vertices of a square are (- 1, 2) and (3, 2). Then the coordinates of the other two vertices are B (1, 0) and D (1, 4). ☛ Related Questions:
Answer : Given :If two opposite vertices of a square are ( 5,4 ) and ( 1,6) To find : the coordinates of its remaining vertices Let B (x, y). We have AB = BC Squaring both sides => AB2 = BC2 => (x-5)2 +(y-4)2 = (x-1)2 +(y-6)2 => x2 +25 -10x +y2 +16 - 8y = x2 +1 -2x + y2 +36 -12y => 4 - 8x +4y =0 =>2x - y =1 .........(1) also AC2 = (5-1)2 + (4-6)2 = 16 + 4 = 20 In right triangle ABC, by Pythagoras theorem, AC2 = AB2+BC2 => AC2 = 2AB2 => 20 = 2 ( (x-5)2 +(y-4)2 ) => 20 = 2 ( x2 + 25 -10x+ y2 +16 -8y ) => 10= x2 + 25 -10x+ y2 +16 -8y => x2 -10x+ y2 -8y + 31 =0 => x2 -10x+ (2x+1)2 - 8(2x+1) + 31 =0 {using eq 1} => x2 -10x+ 4x2 + 1 + 4x -16x-8 + 31 =0 =>5 x2 -22x +24 =0 D = b2 -4ac => D = (-22)2 - 4(5)(24) => D = 484 - 480 => D =4 => D1/2 = 2 x = (-b+D1/2) / 2a , (-b - D1/2) / 2a => x = (22 +2) / 10 , (22-2) / 10 => x = 2.4 , 2 => y = 2x+1 , => y = 5.8 , 5 therefore the points are ( 2.4 , 5.8) and ( 2,5) Answer
Given: Two opposite vertices of a square are $(5, 4)$ and $(1, -6)$. To do: We have to find the coordinates of its remaining two vertices. Solution: Let ABCD be the given square and $A (5, 4)$ and $C (1, -6)$ are the opposite vertices. This implies, $AB=BC=CD=DA$ We know that, The distance between two points \( \mathrm{A}\left(x_{1}, y_{1}\right) \) and \( \mathrm{B}\left(x_{2}, y_{2}\right) \) is \( \sqrt{\left(x_{2}-x_{1}\right)^{2}+\left(y_{2}-y_{1}\right)^{2}} \). Therefore, \( \mathrm{AB}=\mathrm{BC} \) Squaring on both sides, we get, \( \mathrm{AB}^{2}=\mathrm{BC}^{2} \) \( \Rightarrow (x-5)^{2}+(y-4)^{2}=(x-1)^{2}+(y+6)^{2} \) \( \Rightarrow x^{2}-10 x+25+y^{2}-8 y+16 =x^{2}-2 x+1+y^{2}+12 y+36 \) \( \Rightarrow -10 x+2 x-8 y-12 y=37-41 \) \( \Rightarrow -8 x-20 y=-4 \) \( \Rightarrow -4(2 x+5 y)=-4 \) \( \Rightarrow 2 x+5 y=1 \) \( \Rightarrow 2 x=1-5 y \)\( \Rightarrow x=\frac{1-5 y}{2} \) \( \mathrm{ABC} \) is a right angled triangle. \( \Rightarrow \mathrm{AC}^{2}=\mathrm{AB}^{2}+\mathrm{BC}^{2} \)\( \Rightarrow (5-1)^{2}+(4+6)^{2}=x^{2}-10 x+25+y^{2}-8 y +16+x^{2}-2 x+1+y^{2}+12 y+36 \)\( (4)^{2}+(10)^{2}=2 x^{2}+2 y^{2}-12 x+4 y+78 \) \( 16+100=2 x^{2}+2 y^{2}-12 x+4 y+78 \) \( \Rightarrow 2 x^{2}+2 y^{2}-12 x+4 y+78-16-100=0 \) \( \Rightarrow 2 x^{2}+2 y^{2}-12 x+4 y-38=0 \) \( \Rightarrow x^{2}+y^{2}-6 x+2 y-19=0 \) Substituting \( x=\frac{1-5 y}{2} \) \( (\frac{1-5 y}{2})^{2}+y^{2}-6(\frac{1-5 y}{2})+2 y-19=0 \) \( \Rightarrow \frac{1+25 y^{2}-10 y}{4}+y^{2}-3(1-5 y)+2 y-19=0 \) \( \Rightarrow 1+25 y^{2}-10 y+4 y^{2}-12(1-15 y)+8 y-76=0 \) \( \Rightarrow 1+25 y^{2}-10 y+4 y^{2}-12+60 y+8 y-76=0 \) \( \Rightarrow 29 y^{2}+58 y-87=0 \)\( \Rightarrow y^{2}+2 y-3=0 \)\( \Rightarrow y^{2}+3 y-y-3=0 \)\( \Rightarrow y(y+3)-1(y+3)=0 \) \( \Rightarrow(y+3)(y-1)=0 \) \( y+3=0 \) or \( y-1=0 \) \( y=-3 \) or \( y=1 \) If \( y=1, \) then, \( =\frac{1-5 \times 1}{2} \) \( =\frac{1-5}{2} \) \( =\frac{-4}{2} \) \( =-2 \) \( x=\frac{1-5(-3)}{2} \) \( =\frac{1+15}{2} \) \( =\frac{16}{2} \) \( =8 \) > |