Page 16 - E- Book Prim 6

Delta Modern Language Schools Grade 6
Primary stage
Math department
1st term 2024/2025

Unit (3)

Equation and inequality

numbers

Equations and solving equations:Equation: is a mathematical

sentence that uses an equal sign .

Ex : 6 + Y = 9 , 3 X = 21, 17 = N – 8

5 =3,
The equation X +3 = 7, contains one variable “ X “ called “ the unknown”

Solving equations: means finding the value of the unknown which

satisfies the equation.

4 is the solution of the equation X +3 = 7

Remarks :

1 Adding equal amounts to both sides of the equation does not affect
the equality of the equation.

Ex : X-3 = 4 “Add 3 to both sides”, X-3+3 = 4+3 , X = 7

2 Subtracting equal amounts to both sides of the equation does not
affect the equality of the equation.

Ex : X+3 = 8 “Subtract 3 from both sides”, X+3-3 = 8-3 , X = 5

3 Multiplying both sides of the equation by the same natural number
not equal to zero, does not affect the equality of the equation.

Ex: =8 “Multiply both sides by 2”, x2=8x2, X= 16

4 Dividing both sides of the equation by the same natural number not

equal to zero, does not affect the equality of the equation.
Ex: 5X = 10 “Divide both sides by 5”, 5X÷ 5 = 10 ÷ 5 , X = 2

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