Solving By Factorisation PYQs
Overview
This page provides comprehensive Class 10 Maths Solving By Factorisation PYQs | Quadratic Equations. Solving By Factorisation previous year questions for Class 10 Maths Quadratic Equations. Practice CBSE board PYQs with step-by-step solutions on SJMaths.
Practice Previous Year Questions Topic-wise
Q1
2023
00:00
The roots of the equation $x^2 + 3x - 10 = 0$ are:
Factorising:
$x^2+5x-2x-10=0$
$(x+5)(x-2)=0$
$x=-5, 2$
Option (a) $2, -5$
Q2
SA-I 2021–22
00:00
Solve for $x$: $x^2 - 2ax - (4b^2 - a^2) = 0$
Rewrite equation:
$x^2-2ax+a^2-4b^2=0$
$(x-a)^2-(2b)^2=0$
$(x-a-2b)(x-a+2b)=0$
$x=a\pm 2b$
Q3
SA-I 2021–22
00:00
Solve for $x$: $2x^2-2\sqrt2x+1=0$
$a=2, b=-2\sqrt2, c=1$
$D=b^2-4ac=8-8=0$
Roots are real and equal
$x=\frac{-b}{2a}=\frac{2\sqrt2}{4}=\frac{\sqrt2}{2}$
$x=\frac{\sqrt2}{2}$
Q4
SA-II 2016
00:00
Solve for $x$: $\sqrt{2x+9}+x=13$
$\sqrt{2x+9}=13-x$
Squaring both sides:
$2x+9=(13-x)^2$
$x^2-28x+160=0$
$(x-8)(x-20)=0$
Check: $x=8$ valid, $x=20$ rejected
$x=8$
Q5
SA-II 2016
00:00
Solve for $x$: $\sqrt{6x+7}-(2x-7)=0$
$\sqrt{6x+7}=2x-7$
Squaring both sides:
$6x+7=4x^2-28x+49$
$4x^2-34x+42=0$
$(2x-7)(2x-6)=0$
Valid solution: $x=\frac{7}{2}$
$x=\frac{7}{2}$
Q6
SA-II 2016
00:00
Solve: $\dfrac{1}{(x-1)(x-2)}+\dfrac{1}{(x-2)(x-3)}=\dfrac{3}{2}$ ($x\neq1,2,3$)
Taking LCM and simplifying
$2(2x-4)=3(x-1)(x-3)$
$3x^2-16x+17=0$
$x= \frac{17}{3}, 1$
$x=\frac{17}{3}$
Q7
SA-II 2016
00:00
Solve for $x$: $\dfrac{1}{x}+\dfrac{2}{2x-3}=\dfrac{1}{x-2}$
Taking LCM and simplifying
$2x^2-7x+6=0$
$(2x-3)(x-2)=0$
Valid solution: $x=\frac{3}{2}$
$x=\frac{3}{2}$
Q8
SA-II 2019
00:00
Solve: $\dfrac{1}{x+1}+\dfrac{2}{x+2}=\dfrac{7}{x+5}$ ($x\neq-1,-2,-5$)
Taking LCM and simplifying
$x^2+4x+1=0$
$x=-2\pm\sqrt3$
$x=-2\pm\sqrt3$
Q9
SA-II 2017
00:00
Solve for $x$: $\dfrac{1}{x+1}+\dfrac{3}{5x+1}=\dfrac{5}{x+4}$ ($x\neq-1,-\frac15,-4$)
Taking LCM: $(x+1)(5x+1)(x+4)$
$(5x+1)(x+4)+3(x+1)(x+4)=5(x+1)(5x+1)$
$5x^2+21x+4+3x^2+15x+12=25x^2+30x+5$
$17x^2-6x-11=0$
$(17x+11)(x-1)=0$
Valid solution: $x=1$
$x=1$
Q10
SA-II 2016
00:00
Solve the quadratic equation: $x^2+\left(\frac{a+b}{a}+\frac{a}{a+b}\right)x+1=0$
Let $\alpha=\frac{a+b}{a}$ and $\beta=\frac{a}{a+b}$
Then equation becomes: $x^2+(\alpha+\beta)x+1=0$
Since $\alpha\beta=1$, roots are $-\alpha$ and $-\beta$
$x=-\frac{a+b}{a}$ or $x=-\frac{a}{a+b}$
Q11
2024
00:00
Case Study: A rectangular floor can be tiled using 200 square tiles. If the side of each tile is increased by 1 unit, only 128 tiles are required.
(i) Form the quadratic equation.
(ii) Write it in standard form.
(iii) Find the value of $x$ by factorisation.
(i) Form the quadratic equation.
(ii) Write it in standard form.
(iii) Find the value of $x$ by factorisation.
Let side of tile = $x$ units
Area of floor = $200x^2$
New area = $128(x+1)^2$
$200x^2=128(x+1)^2$
$25x^2=16(x^2+2x+1)$
$9x^2-32x-16=0$
$(9x+4)(x-4)=0$
$x=4$ (reject $x=-\frac49$)
Side of tile = 4 units
Q12
SA-I 2023
00:00
Solve the quadratic equation: $2x^2-2\sqrt2x+1=0$
$a=2, b=-2\sqrt2, c=1$
$D=b^2-4ac=8-8=0$
Roots are real and equal
$x=\frac{-b}{2a}=\frac{\sqrt2}{2}$
$x=\frac{\sqrt2}{2}$
Q13
SA-II 2016
00:00
Solve for $x$: $\sqrt{2x+9}+x=13$
$\sqrt{2x+9}=13-x$
Squaring both sides
$2x+9=(13-x)^2$
$x^2-28x+160=0$
$(x-8)(x-20)=0$
Valid solution: $x=8$
$x=8$
Q14
SA-II 2016
00:00
Solve for $x$: $\sqrt{6x+7}-(2x-7)=0$
$\sqrt{6x+7}=2x-7$
Squaring both sides
$6x+7=4x^2-28x+49$
$2x^2-17x+21=0$
$(2x-7)(x-3)=0$
Valid solution: $x=\frac72$
$x=\frac72$
The roots of the equation $x^2 + 3x - 10 = 0$ are:
Factorising:
$x^2+5x-2x-10=0$
$(x+5)(x-2)=0$
$x=-5, 2$
Option (a) $2, -5$
Q2
SA-I 2021–22
00:00
Solve for $x$: $x^2 - 2ax - (4b^2 - a^2) = 0$
Rewrite equation:
$x^2-2ax+a^2-4b^2=0$
$(x-a)^2-(2b)^2=0$
$(x-a-2b)(x-a+2b)=0$
$x=a\pm 2b$
Q3
SA-I 2021–22
00:00
Solve for $x$: $2x^2-2\sqrt2x+1=0$
$a=2, b=-2\sqrt2, c=1$
$D=b^2-4ac=8-8=0$
Roots are real and equal
$x=\frac{-b}{2a}=\frac{2\sqrt2}{4}=\frac{\sqrt2}{2}$
$x=\frac{\sqrt2}{2}$
Q4
SA-II 2016
00:00
Solve for $x$: $\sqrt{2x+9}+x=13$
$\sqrt{2x+9}=13-x$
Squaring both sides:
$2x+9=(13-x)^2$
$x^2-28x+160=0$
$(x-8)(x-20)=0$
Check: $x=8$ valid, $x=20$ rejected
$x=8$
Q5
SA-II 2016
00:00
Solve for $x$: $\sqrt{6x+7}-(2x-7)=0$
$\sqrt{6x+7}=2x-7$
Squaring both sides:
$6x+7=4x^2-28x+49$
$4x^2-34x+42=0$
$(2x-7)(2x-6)=0$
Valid solution: $x=\frac{7}{2}$
$x=\frac{7}{2}$
Q6
SA-II 2016
00:00
Solve: $\dfrac{1}{(x-1)(x-2)}+\dfrac{1}{(x-2)(x-3)}=\dfrac{3}{2}$ ($x\neq1,2,3$)
Taking LCM and simplifying
$2(2x-4)=3(x-1)(x-3)$
$3x^2-16x+17=0$
$x= \frac{17}{3}, 1$
$x=\frac{17}{3}$
Q7
SA-II 2016
00:00
Solve for $x$: $\dfrac{1}{x}+\dfrac{2}{2x-3}=\dfrac{1}{x-2}$
Taking LCM and simplifying
$2x^2-7x+6=0$
$(2x-3)(x-2)=0$
Valid solution: $x=\frac{3}{2}$
$x=\frac{3}{2}$
Q8
SA-II 2019
00:00
Solve: $\dfrac{1}{x+1}+\dfrac{2}{x+2}=\dfrac{7}{x+5}$ ($x\neq-1,-2,-5$)
Taking LCM and simplifying
$x^2+4x+1=0$
$x=-2\pm\sqrt3$
$x=-2\pm\sqrt3$
Q9
SA-II 2017
00:00
Solve for $x$: $\dfrac{1}{x+1}+\dfrac{3}{5x+1}=\dfrac{5}{x+4}$ ($x\neq-1,-\frac15,-4$)
Taking LCM: $(x+1)(5x+1)(x+4)$
$(5x+1)(x+4)+3(x+1)(x+4)=5(x+1)(5x+1)$
$5x^2+21x+4+3x^2+15x+12=25x^2+30x+5$
$17x^2-6x-11=0$
$(17x+11)(x-1)=0$
Valid solution: $x=1$
$x=1$
Q10
SA-II 2016
00:00
Solve the quadratic equation: $x^2+\left(\frac{a+b}{a}+\frac{a}{a+b}\right)x+1=0$
Let $\alpha=\frac{a+b}{a}$ and $\beta=\frac{a}{a+b}$
Then equation becomes: $x^2+(\alpha+\beta)x+1=0$
Since $\alpha\beta=1$, roots are $-\alpha$ and $-\beta$
$x=-\frac{a+b}{a}$ or $x=-\frac{a}{a+b}$
Q11
2024
00:00
Case Study: A rectangular floor can be tiled using 200 square tiles. If the side of each tile is increased by 1 unit, only 128 tiles are required.
(i) Form the quadratic equation.
(ii) Write it in standard form.
(iii) Find the value of $x$ by factorisation.
(i) Form the quadratic equation.
(ii) Write it in standard form.
(iii) Find the value of $x$ by factorisation.
Let side of tile = $x$ units
Area of floor = $200x^2$
New area = $128(x+1)^2$
$200x^2=128(x+1)^2$
$25x^2=16(x^2+2x+1)$
$9x^2-32x-16=0$
$(9x+4)(x-4)=0$
$x=4$ (reject $x=-\frac49$)
Side of tile = 4 units
Q12
SA-I 2023
00:00
Solve the quadratic equation: $2x^2-2\sqrt2x+1=0$
$a=2, b=-2\sqrt2, c=1$
$D=b^2-4ac=8-8=0$
Roots are real and equal
$x=\frac{-b}{2a}=\frac{\sqrt2}{2}$
$x=\frac{\sqrt2}{2}$
Q13
SA-II 2016
00:00
Solve for $x$: $\sqrt{2x+9}+x=13$
$\sqrt{2x+9}=13-x$
Squaring both sides
$2x+9=(13-x)^2$
$x^2-28x+160=0$
$(x-8)(x-20)=0$
Valid solution: $x=8$
$x=8$
Q14
SA-II 2016
00:00
Solve for $x$: $\sqrt{6x+7}-(2x-7)=0$
$\sqrt{6x+7}=2x-7$
Squaring both sides
$6x+7=4x^2-28x+49$
$2x^2-17x+21=0$
$(2x-7)(x-3)=0$
Valid solution: $x=\frac72$
$x=\frac72$