Question

(ii) 21 - 3(x - 7) = x + 20. solve linear equation​

Answer 1

Answer:

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

21-3x+21=x+20

x+3x=20-42

4x=22

x=22/4

x=11/2

hope it helps

Answer 2

• Linear Equation

• $\sf{21 - 3(x - 7) = x + 20}$

• Solution

$: \implies{\sf{21 - 3(x - 7) = x + 20}}$

$: \implies{\sf{21 - 3x \: +21 = x + 20}}$

$: \implies{\sf{42 - 3x = x + 20}}$

$: \implies{\sf{42 - 20 = x + 3x}}$

$: \implies{\sf{22 = 4x}}$

$: \implies{\sf{ \dfrac{22}{4} = x}}$

$: \implies{\sf{ \dfrac{ \cancel{22}}{ \not{4}} = x}}$

$: \implies{\sf{5.5 = x}}$

$\red{\bigstar}$ $\large{\boxed{\bf{\green{x = 5.5}}}}$

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