Question

III. True or False :
1. (-90) + (-30) = 60
2. (-45) - (-8) = (-8) – (-45)
3. (-15) x 5 = 75
4. x + (-x) = 0
5. Sum of a-b+c and -a+b-c is zero.
TTT
11.in
no
oction​

Answer 1

Answer:

1 false

2 false

3 false

4 true

5 true

Step-by-step explanation:

please make me brainlist

Answer 2

|||. True or False :

(i). ( - 90 ) + ( - 30 ) = 60

• Multiplying the signs and opening the brackets

$\sf\to\:-90-30=-60$

$\sf\to\:-120=-60$

Therefore , LHS ≠ RHS

Henceforth it's $\sf\color{red}{False}$ .

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(ii). ( - 45 ) - ( - 8 ) = ( - 8 ) - ( - 45 )

• Multiplying the signs and opening the brackets

$\sf\to\:-45+8=-8+45$

$\sf\to\:-37=37$

Therefore , LHS ≠ RHS [ Though the number matches, the signs differ ]

Henceforth it's $\sf\color{red}{False}$ .

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(iii). ( - 15 ) × 5 = 75

• Multiplying the numbers

$\sf\to\:-75=75$

Therefore , LHS ≠ RHS [ Though the number matches, the signs differ ]

Henceforth it's $\sf\color{red}{False}$ .

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(iv). x + ( - x ) = 0

• Multiplying the signs and opening the brackets

$\sf\to\:x-x=0$

• Terms with opposite signs gets cancelled out

$\sf\to\:\cancel{x}-\cancel{x}=0$

$\sf\to\:0=0$

Therefore , LHS = RHS.

Henceforth it's $\sf\color{red}{True}$ .

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(v). Sum of (a - b + c) and (-a + b - c) is zero.

$\sf\:a-b+c+(-a+b-c) =0$

• Multiplying the signs and opening the brackets

$\sf\to\:a-b+c-a+b-c=0$

• Arranging the terms and doing simple calculations

$\sf\to\:a-a-b+b+c-c=0$

• Terms with opposite signs gets cancelled out

$\sf\to\:\cancel{a}-\cancel{a}-\cancel{b}+\cancel{b}+\cancel{c}-\cancel{c}=0$

$\sf\to\:0=0$

Therefore , LHS = RHS.

Henceforth it's $\sf\color{red}{True}$ .

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!! Hope it helps !!