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-3x + 4y = 7
2x + y = -1
Elimination method

1 Answer

5 votes


\huge{ \mathfrak{ \underline{ Answer \: \: ✓ }}}

The equations are :

-3x + 4y = 7. - [1]

2x + y = -1 - [2]


\underline{ \underline{ \bf{step} - 1}}

multiply equation [2] with 4


\longrightarrow(2x + y = -1 ) * 4


\longrightarrow8x + 4y = - 4


\underline{ \underline{ \bf{step} -2}}

subtract equation [1] from [2]


\longrightarrow8x + 4y - ( - 3x + 4y) = - 4 - 7


\longrightarrow8x + 4y + 3x - 4y = - 11


\longrightarrow11x = - 11


\longrightarrow \: x = - 1


\underline{ \underline{ \bf{step} - 3}}

plugging the value of x in equation [1]


\longrightarrow- 3x + 4y = 7


\longrightarrow - (3 * - 1) + 4y = 7


\longrightarrow3 + 4y = 7


\longrightarrow4y = 4


\longrightarrow \: y = 1


\#TeeNForeveR

User Jamesdlin
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