Question

4x-3y= 7
2x + 4y = 18​

Answer 1

Given

• 4x - 3y = 7⠀⠀⠀⠀.....[1]
• 2x + 4y = 18⠀⠀⠀⠀....[2]

Solution

$\sf{⟶}$ We will solve this question by using Elimination method.

★ Multiplying 2 to 2nd equation

$\tt\longmapsto{(2x + 4y = 18) \times 2}$

$\tt\longmapsto{4x + 8y = 36}$⠀⠀....[3]

★ Subtracting eq [1] from eq [3]

$\tt:\implies{\cancel{4x} + 8y = 36}$

$\tt:\implies{\cancel{4x} - 3y = 7}$

$\tt\longmapsto{\: \: \: + 11y = 29}$

⠀

$\tt:\implies{\: \: \: \: y = \dfrac{29}{11}}$

⠀

★ Putting the value of y in eq [1]

$\tt:\implies\: \: \: \: \: \: \: \: {4x - 3(\dfrac{29}{11}) = 7}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {4x - \dfrac{87}{11} = 7}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {4x = 7 \times \dfrac{11}{87}}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {4x = \dfrac{77}{87}}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {x = \dfrac{77}{87 \times 4}}$

⠀

$\tt:\implies\: \: \: \: \: \: \: \: {x = \dfrac{77}{348}}$

⠀

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