Class 8 Maths

# Linear Equations

## Exercise 2.1 (NCERT)

### Solve the following equations:

Question 1: x-2=7

Solution: Given x-2=7

By adding 2 to both sides we get:

x-2+2=7+2

Or, x=9

Question 2: y+3=10

Solution: Given y+3=10

By subtracting 3 from both sides we get:

y+3-3=10-3

Or, y=7

Question 3: 6=z+2

Solution: Given 6=z+2

By subtracting 2 from both sides we get:

6-2=z+2-2

Or, 4=z

Or, z=4

Question 4: 3/7+x=(17)/(7)

Solution: Given 3/7+x=(17)/(7)

By subtracting 3/7 from both sides we get:

3/7+x-3/7=(17)/(7)-3/7

Or, x+3/7-3/7=(17)/(7)-3/7

Or, x=(17-3)/(7)=(14)/(7)=2

Question 5: 6x=12

Solution: Given 6x=12

After dividing both sides by 6 we get:

(6x)/(6)=(12)/(6)

Or, x=2

Question 6: t/5=10

Solution: Given t/5=10

By multiplying both sides by 5 we get:

t/5xx5=10xx5

Or, t=50

Question 7: (2x)/(3)=18

Solution: Given (2x)/(3)=18

By multiplying both sides by 3 we get:

(2x)/(3)xx3=18xx3

Or, 2x=54

By dividing both sides by 2 we get:

(2x)/(2)=(54)/(2)

Or, x=27

Question 8: 1.6=(y)/(1.5)

Solution: Given 1.6=(y)/(1.5)

By multiplying both sides by 1.5 we get:

1.6xx1.5=(y)/(1.5)xx1.5

Or, 2.4=y

Or, y=2.4

Question 9: 7x-9=16

Solution: Given 7x-9=16

By adding 9 on both sides we get:

7x-9+9=16+9

Or, 7x=25

By dividing both sides by 7 we get:

(7x)/(7)=(25)/(7)

Or, x=(25)/(7)

Question 10: 14y-8=13

Solution: Given 14y-8=13

Adding 8 on both sides we get:

14y-8+8=13+8

Or, 14y=21

Dividing both sides by 14 we get:

(14y)/(14)=(21)/(14)

Or, y=3/2

Question 11: 17+6p=9

Solution: Given 17+6p=9

Subtracting 17 from both sides we get:

17+6p-17=9-17

Or, 6p+17-17=-8

Or, 6p=-8

Dividing both sides by 6 we get:

(6p)/(6)=(-8)/(6)

Or, p=-4/3

Question 12: x/3+1=(7)/(15)

Solution: Given x/3+1=(7)/(15)

Subtracting 1 from both sides we get:

x/3+1-1=(7)/(15)-1

Or, x/3=(7-15)/(15)

Or, x/3=(-8)/(15)

Multiplying both sides by 3 we get:

x/3xx3=(-8)/(15)xx3

Or, x=-8/5

## Rational Numbers

Any number which can be expressed in the form of p/q where q ≠ 0 is called rational number.

## Linear Equations

A linear equation is an equation in which the highest power of the variable is always 1. It is also known as a one-degree equation.

A plane figure bounded by a finite straight line segment in loop to form a closed chain is called a polygon.

## Data Handling

Learn about arranging data and making bar chart, histogram and pie chart.

## Probability

Probability of an outcome out of total events.

## Cube Roots

A number which is equal to another number raised to the power 3 is called a perfect cube.

## Algebraic Expressions

An expression with coefficient and variables is called algebraic expression.

## Mensuration

Learn to calculate area and perimeter of two-dimensional figures.

## Exponents Power

Exponents are used to represent a large number in simpler form.

## Proportion

A part compared to the whole is called proportion.

## Factorization

Factorization consists of writing a number or another mathematical object as a product of several factors, usually smaller or simpler objects of the same kind.

## Graph

A graph is a pictorial representation of data to make it more user friendly.