91Ó°ÊÓ

Real numbers are simply the combination of Whole numbers, Integers, Rational and Irrational numbers in the number system.

Suppose a, b, and c is three real numbers.

Distributive Property of Multiplication

Property: $(  \text{b}  +  \text{c}  ) (- \text{a} ) =  \text{b}  ·  (- \text{a} )  +  \text{c}  ·  (- \text{a} )  \text{=}  -\text{b}  ·  \text{a}  -  \text{c}  ·  \text{a}$

Example: $\text{(8}  +  \text{5}  \text{)}  (-  3)=  8 · (-3)  +  5 ·  (-3)  =  -24-15=-  39$

We can write 4.02 as (4 + 0.02), to evaluate the expression (4.02)(– 9), we can use the distributive method of multiplication.

Distributive Property of Multiplication

Property: $(  \text{b}  +  \text{c}  ) (- \text{a} ) =  \text{b}  ·  (- \text{a} )  +  \text{c}  ·  (- \text{a} )  \text{=}  -\text{b}  ·  \text{a}  -  \text{c}  ·  \text{a}$

localid="1649117560616" $\begin{array}{l}\text{ (}4.02\text{ â¶Ä‰) }(−\text{ â¶Ä‰9})\text{ }=\text{ â¶Ä‰}(4\text{ â¶Ä‰}+\text{ â¶Ä‰}0.02)\text{ â¶Ä‰}(−\text{ }9)\text{ }=\text{ â¶Ä‰}4\text{ â¶Ä‰}·\text{ â¶Ä‰}(−9)\text{ â¶Ä‰}+\text{ â¶Ä‰}0.02\text{ â¶Ä‰}(−9)\text{ â¶Ä‰}=\text{ â¶Ä‰}−\text{ â¶Ä‰}36\text{ â¶Ä‰}−\text{ â¶Ä‰}0.18\text{ â¶Ä‰}=\text{ â¶Ä‰}−\text{ â¶Ä‰}36.18\\ \text{ (}4.02\text{ â¶Ä‰) }(−\text{ â¶Ä‰9})\text{ }=-\text{ â¶Ä‰}36.18\end{array}$