chapter-header
Jump to
Home > Selina Solutions Class 9 Mathematics > Chapter 1 - Chapter 1- Rational and Irrational Numbers > Exercise 1(D) > Question 6

Selina Solutions Class 9 Mathematics Solutions for Exercise 1(D) in Chapter 1 - Chapter 1- Rational and Irrational Numbers

question-prev Prev
Question 6 Exercise 1(D)
Next question-next

Draw a line segment of length √𝟓 cm.

Answer:

We know that \sqrt{5}=\sqrt{2^{2}+1^{2}}

Which relates to: Hypotenuse= \sqrt{\text { Side } 1^{2}+\text { Side } 2^{2}} \text { [Pythagoras theorem] }

Hence, Considering Side 1=2 and Side 2 =1,

We get a right angled triangle such that:

∠𝐴=90°, AB=2cm and AC=1cm

Selina Solutions CONCISE Maths - Class 9 ICSE chapter Chapter 1- Rational and Irrational Numbers Question 6 Solution image

Video transcript
"hello students welcome to lido learning today we are going to do the question which is on the screen draw a line segment of length under root 5 centimeter now we know that under root 5 is an irrational number so we cannot use a ruler or a scale to draw a line of this length so what are we going to do we are going to use the pythagoras theorem in mathematics to draw this line so let us see how we can use this theorem so we know that under root of 5 whole square is equal to 2 whole square plus 1 whole square now if you remember the right angle triangle this is the right angle triangle and this is what we can use to draw a length now pythagoras theorem is applicable on a right angle triangle now using this equation we can see that the hypotenuse of any right angle triangle the whole square of it is equal to the sum of the squares of the length and the base of the right angle triangle now using this we can say that's if at all we can create a right angle triangle of this nature then the length this length is going to be the size under root of 5 centimeter so this is how we can do this question and draw a line of under root 5 centimeter if you have any concerns please message below this video and subscribe to this channel thank you"
Related Questions
Exercises
Exercise 1(A)
Exercise 1(B)
Exercise 1(C)
Exercise 1(D)
Chapters
Chapter 1- Rational and Irrational Numbers
Chapter 2- Compound Interest [Without Using Formula
Chapter 3- Compound Interest [Using Formula
Chapter 4- Expansions
Chapter 5- Factorisation
Chapter 6- Simultaneous Equations
Chapter 7- Indices [exponents]
Chapter 8- Logarithms
Chapter 9- Triangles [Congruency in Triangles]
Chapter 10- Isosceles Triangle
Chapter 11- Inequalities
Chapter 12- Mid-Point and Its Converse
Chapter 13- Pythagoras Theorem
Chapter 14- Rectilinear Figures
Chapter 15- Construction of Polygons
Chapter 16- Area Theorems
Chapter 17- Circles
Chapter 18- Statistics
Chapter 19- Mean and Median
Chapter 20- Area and Perimeter of Plane Figures
Chapter 21- Solids
Chapter 22- Trigonometrical Ratios
Chapter 23- Trigonometrical Ratios of Standard Angles
Chapter 24- Solution Of Right Triangles
Chapter 25- Complementary angles
Chapter 26- Co-ordinate Geometry
Chapter 27- Graphical Solution
Chapter 28- Distance Formula
lido-difference

Lido

Courses

Teachers

Book a Demo with us

Syllabus

Quick Links

Terms & Policies

Terms & Policies

Selina Question Bank

Maths
Physics
Biology

Allied Question Bank

Chemistry
Connect with us on social media!
2022 © Quality Tutorials Pvt Ltd All rights reserved