Question

solve the substitution method and elimation method x+y=2 2x-y=8​

Answer 1

Solution :

⠀⠀⠀⠀⠀By Method of Substitution :

Equations :

⠀⠀⠀⠀⠀• x + y = 2 .......(1)

⠀⠀⠀⠀⠀• 2x - y = 8 ......(2)

From Equation (1)

›› x = 2 - y ....(3)

⠀⠀⠀⠀⠀Substituting value of x in (2)

›› 2(2 - y) - y = 8

›› 4 - 2y - y = 8

›› - 3y = 4

• y = -4/3

Substituting value of y in (3)

⇛x = 2 - (-4/3)

⇛x = 2 + 4/3

⇛x = (6 + 4)/3

• x = 10/3

⠀⠀⠀⠀⠀By Method of Elimination :

Equations :

⠀⠀⠀⠀⠀• x + y = 2 .......(1)

⠀⠀⠀⠀⠀• 2x - y = 8 ......(2)

⠀⠀⠀⠀⠀x + y = 2

⠀⠀⠀⠀⠀2x - y = 8

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀

⠀⠀⠀⠀⠀3x⠀⠀= 10

⠀⠀⠀⠀⠀⠀x ⠀ = 10/3

⠀⠀⠀⠀⠀Substituting value of x in (1)

⇛x + y = 2

⇛10/3 + y = 2

⇛(10 + 3y)/3 = 2

⇛10 + 3y = 6

⇛3y = 6 - 10

⇛3y = - 4

• y = -4/3

$\large\dag \large { \red{\underline{\bf{Hence }}}}$

• value of x is 10/3
• value of y is - 4/3

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