Algebraic Expressions
The algebraic expression contains constants, variables, and operations, such as multiplication, division, and addition.
A variable is an unknown number. They are generally expressed using letters like x, y, n, etc. A constant number is a number without any variables.
When a number follows a variable, it is called its Coefficient. Terms are separated by operators and can be numbers or variables.
Equation
An equation identifies two expressions as having the same value.
Linear Expression
A linear expression has a maximum power of 1 and is a variable function.
Example - 4x + 2, 4y etc.
Linear Equations
Linear equations represent straight lines. But, possibly, two variables have a relationship.
A few things to know about linear equations
- The linear equation has a sign of equality. In mathematics, the left-hand side (LHS) and right-hand side (RHS) of the equal sign denote the left-hand and right-hand sides.
- For most equation values, the LHS is equal to the RHS. For some values of the equation, however, this is not true, and these are the values of the solution.
Linear Equations in One Variable Sample Questions for Class 8
Question 1
A 70 m long log is cut into three pieces.
Second piece is 10 more than first piece.
Third piece is 10 less than second piece.
What is measurement of each log?
A. 20,30,20
B. 10,60,10
C. 15,15,40
D. 20,40,10
Question 2
The sum of three consecutive multiple of 9 is 243.
Find the numbers.
A. 72,81,90
B. 63,72,81
C. 45,54,63
D. 36,45,54
Question 3
Reema's age is 4 times age of Rohan.
Rohan is 3 years older to Raina.
Two years before sum of their ages was 27.
How old is Reema?
A. 24 years
B. 35 years
C. 18 years
D. 43 years
Question 4
3/5th of the number is 10 more than two times 40.
Find the number.
A. 165
B. 145
C. 150
D. 135
Question 5
The ages of Rashmi and Rajesh are in ratio 5:6.
Four years later their ages will be 129 years.
What was their ages 4 years ago?
A. 45,56
B. 51, 62
C. 56,68
D. 62,74