Question

solve linear equation for x+ y= 4 nd x- y= 8​

Answer 1

Answer:

x= 6, y= -2

Step-by-step explanation:

x-y = 8

x+y = 4

‐-----------

2x = 12

x = 12/ 2

x = 6

therfore

x= 6

x+y = 4

6+y = 4

y = 4-6

y = -2

Therefore,

x=6, y=(-2)

Answer 2

Given

• Linear equations :-
• x + y = 4⠀⠀....[1]
• x - y = 8⠀⠀ ....[2]

⠀

Solution

• We have two Linear equations.

⠀

$\: \: \: \: \: \: \: \: \: \:\underline{\sf{\red{By\: elimination\: method}}}$

⠀

• Subtracting [1] from [2]

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {(x - y) - (x + y) = 8 - 4}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {\cancel{x} - y - \cancel{x} - y = 4}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {-2y = 4}$

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$\tt:\implies\: \: \: \: \: \: \: \: {y = \dfrac{4}{-2}}$

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$\bf:\implies\: \: \: \: \: \: \: \: {y = -2}$

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• Substituting the value of y in [1]

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$\tt:\implies\: \: \: \: \: \: \: \: {x + (-2) = 4}$

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$\tt:\implies\: \: \: \: \: \: \: \: {x = 4 + 2}$

⠀

$\bf:\implies\: \: \: \: \: \: \: \: {x = 6}$

⠀

Hence,

• x = 6
• y = -2