### Common Errors in Secondary Mathematics

Common Errors Committed  by the  Students  in Secondary Mathematics   Errors  that students often make in doing secondary mathematics  during their practice and during the examinations  and their remedial measures are well explained here stp by step.  Some Common Errors in Mathematics

### Math Assignment Class X Ch-4 | Quadratic Equations

Math Assignment / Class X / Chapter 4 /  Quadratic Equations

Extra questions of chapter 4 class 10 Quadratic Equations with answer and  hints to the difficult questions. Important and useful math assignment for the students of class 10

For better results

• Students should learn all the basic points of  Quadratic Equations
• Student should revise N C E R T book thoroughly with examples.
• Now revise this assignment. This assignment integrate the knowledge of the students.

ASSIGNMENT FOR 10 STANDARD QUADRATIC EQUATIONS

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 Question 36Out of a number of Saras birds, (1/4)th of the number are moving about in Lotus plants, (1/9)th coupled with (1/4)th,  as well as 7 times the square root of the number moving on a hill, 56 birds remain on trees.   What is the total number of words. SolutionLet total birds = x No. of birds moving in lotus plant = (1/4)x No. of birds coupled with = (1/9 +1/4)x = (13/36)x No of birds moving on the hill = 7x No. of birds on the tree = 56 Acoording to the question $\frac{1}{4}x+\frac{13}{36}x+7\sqrt{x}+56=x$ $\frac{22}{36}x+7\sqrt{x}+56=x$ $x-\frac{22}{36}x-7\sqrt{x}-56=0$ $\frac{14}{36}x-7\sqrt{x}-56=0$ $\frac{2}{36}x-\sqrt{x}-8=0$ $\frac{1}{18}x-\sqrt{x}-8=0$ $x-18\sqrt{x}-144=0$ $Putting \: \: \: \: \sqrt{x}=y \: \: \: \Rightarrow\: \: x=y^{2}$ $y^{2}-18y-144=0$ $y^{2}-24y+6y-144=0$ $y(y-24)+6(y-24)=0$ $(y-24)(y+6)=0$$\Rightarrow y=24, -6$ $y=-6 \: \: is \: \: rejected$ $y=\sqrt{x}=24\Rightarrow x=(24)^{2}=576$ Hence Total Number of birds = 576
 Question : 37 7 years ago, age of Varun was five times the square of the age of Swati. After 3 years, age of Swati will be 2/5 of the age of Varun. Find their present ages. Solution : Let 7 years ago the age of Swati = x years Let 7 years ago the age of Varun = y years ATQ       y = 5x2 …………………(1) Present age of Swati = x + 7 Present age of Varun = y + 5 After 3 years age of Swati = x + 10 After 3 years age of Varun= y + 10 Again ATQ :  Age of Swati = (2/5) age of Varun x + 10 = (2/5)[y + 10] 5(x + 10) = 2y + 20 5x + 50 = 2y + 20 Putting  y = 5x2  we get 5x + 50 = 2(5x2 ) + 20 10x2  - 5x + 20 - 50 = 0 10x2 - 5x - 30 = 0 2x2 - x - 6 = 0    (Dividing by 5) (2x + 3)(x - 2) = 0 x = - 3/2 (Rejected)     and   x = 2 Putting x = 2 in equation (1) we get y = 5 (2)2    ⇒     y = 20 Present age of Swati = x + 7  = 2 + 7 = 9 Present age of Varun = y + 7 =  20 + 7 = 27