Question

2x+3y=30 and 8x-y=68 by substitution

Answer 1

Answer:

Add the equations to eliminate the y-term and then solve for x. Substitute the value for x into one of the original equations to find y. Check your answer by substituting x = 8 and y = 2 into the original system.

Answer 2

$\bf{\underline{\underline{Question}}}$

2x+3y=30 and 8x-y=68 by Substitution Method.

$\bf{\underline{\underline{Solution}}}$

Multiplying equation by 4:-

$\bf{4(2x+3y\:=\:30)}$

$\bf{1(8x-\:\:y\:=\:68)}$

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$\bf{8x\:+12y\:=\:120}........................1$

$\bf{8x\:-\:\:\:y\:\:\:=\:\:68}........................2$

$\bf{-\:\:\:-\:\:\:\:\:\:\:=\:-}$

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Subtracting Equation,

$\bf{\cancel8x+12y\:=\:120}$

$\bf{\cancel8x+\:\:y\:\:\:\:=\:\:68}$

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$\bf{13y\:=\:52}$

$\bf{\:y\:\:\:\:=\:\cancel\frac{52}{13}}$

$\bf{\boxed{\:y\:\:\:\:=\:4}}$

Putting value of y in 1 equation.

$\bf{8x+12(4)\:=\:120}$

$\bf{8x+48\:=\:120}$

$\bf{8x\:=\:120-48}$

$\bf{8x\:=\:72}$

$\bf{x\:=\:\cancel\frac{72}{8}}$

$\bf{\boxed{x\:=\:9}}$

$\bf{\underline{\underline{Thanks}}}$