Important Theorems in Mathematics class 10th 2021 and questions for class 10th Board exam 2021 CBSE.

Just in this Article we will also provide you with A Mind map of Mapping Portion for Your Class 10th Board exam in the end of Article. You can download the PDF from there.

In this article we are going to tell and give you some important theorems and questions that you must practice before your board examination . We are here not providing solutions of any question but if more than 250 people or students  comment down asking for solutions ,we will then definitely publish another post with solution or will just attach a SOLUTIONS PDF in this article

So let’s begin

Q1. If two lines intersect then vertically opposite angles are equal.

Q2. If one side of a triangle is produced then the  exterior angle so formed is equal to the sum of two opposite interior angles .

Q3. Prove that the diagonals of a rectangle are equal.

Q4. Prove that the diagonals of a rhombus are perpendicular to each other.

Q5. Equal cords of a circle subtend equal angles at the centre.

Q6. The sum of either pair of the opposite angles of a cyclic quadrilateral is 180 °.

Q7. Simplify : 2√45 + 3√20

2√5

Q 8. If D(5,-3) ,E(5,3) and F(6,6) are the midpoints of the sides of ΔABC . Then find the area of the triangle ABC .

Q9. If α β Y are the zeros of P(x) = 18x^3 -15x^2 -x+2
then find the value of        1     +    1   +    1                                                          αβ       βY      Yα
Q10.

Options  a. 1      b.2     c. 3   d.4

Q11.

Q12 .

Q13.

Q14.

Q15. Find the ratio in which the line segment joining the points (6,4) and (1,-7) is divided by the X-axis.

Q16. If the angle of elevation from a point 60m above a lake to a cloud is 30° and the angle of depression of the cloud’s reflection in the lake is 60 ° , then find the distance of the cloud above the lake.

Q17. If the sum of the first 6 terms of an AP  is 36 and that of the first 16 terms is 256, find the sum of first 11 terms.

Q18. Find the co-ordinates of the points of trisection of the line segment joining the points (3,-1) and (6,8).

Q19. Find the area of a quadrilateral ABCD having vertices at A(1,2) , B(1,0), C(4,0) ,D(4,4).

Q20. The  angle of elevation of an airplane from point A on the ground is 60 °. After a flight of 10 seconds , on the same height , the angle of elevation from point A becomes 30 ° . If the airplane is flying at the speed of 720km/hr, find the constant  height at which the airplane is flying.

Q21.

Hey guys I am sorry for not uploading or  attaching PDF of these questions’ solutions ,because you yourself need to practise these questions  and try to do all the problems on your  own , don’t take anyone’s help. But still as stated above ,if more 250 people or students ask for the solutions in the comment section , I will definitely upload or add their solutions.

Thanks for staying here.