Question

please solve this question ​

Answer 1

$\large{\mathfrak{\underline{\underline{Answer :-}}}}$

Given :-

⇒ 21 - 3(x - 7) = x + 20

To Find :-

Value of x

Solution :-

⇒ 21 - 3(x - 7) = x + 20

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We know that if there is negative sign before bracket than the sign got changed.

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⇒ 21 - 3x + 21 = x + 20

⇒ 21 + 21 - 20 = x + 3x

⇒ 42 - 20 = 4 x

⇒ 22 = 4x

⇒ x = 22/4

⇒ x = 5.5

$\huge{\boxed{\ x \: = \: 5.5}}$

$\large{\mathfrak{\underline{\underline{verification :-}}}}$

⇒ 21 - 3(x - 7) = x + 20 ........[1]

Putting value of x in equation 1

⇒ 21 - 3(5.5) + 21 = 5.5 + 20

⇒ 21 - 16.5 + 21 = 25.5

⇒ 4.5 + 21 = 25.5

⇒ 25.5 = 25.5

Hence Proved

Answer 2

Answer:

Value of x = 5.5

Step-by-step explanation:

Given simple equation:

21-3(x-7)=x+20

/* Open the bracket ,we get

=> 21-3x+21=x+20

=> 42-3x=x+20

/* Subtract 42 both sides of the equation, we get

=> -42+42-3x=x+20-42

=> -3x = x-22

/* Subtract x both sides of the equation, we get

=> -x-3x = -x+x-22

=> -4x = -22

/* Divide each term by (-4), we get

$\implies \frac{-4x}{-4}=\frac{-22}{-4}$

$\implies x = \frac{22}{4}\\=\frac{11}{2}\\=5.5$

Therefore,

Value of x = 5.5

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