Question

If a= -6 and b= -9 show that (a-b) is not equal (b-a).


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Answer 1

Answer:

26

Step-by-step explanation:

Method 1: Squaring & adding the given equations  a+b=6  &  a−b=4  , one should get

(a+b)2+(a−b)2=62+42  

a2+b2+2ab+a2+b2−2ab=36+16  

2(a2+b2)=52  

a2+b2=522=26  

Method 2: Adding the given equations:  a+b=6  &  a−b=4  ⟹a+b+a−b=6+4⟹a=5  

Now, subtracting given equations:  a+b−a+b=6−4⟹b=1  

∴a2+b2=52+12=25+1=26

Answer 2

Solution:

Given ,

• a = - 6
• b = - 9

Need to show

• a - b ≠ b - a

Here , substituting the value of a & b

Firstly a - b

→ - 6 - ( - 9)

→ - 6 + 9

→ a - b = 3

Now , b - a

→ - 9 - ( - 6)

→ - 9 + 6

→ b - a = - 3

By comparing

3 ≠ - 3

a - b ≠ b - a

Hence, proved !

Note : Here , when the values of a & b are equal then a = b.