Question

5x + 4y - 4 = 0
x - 20 = 12y.​

Answer 1

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$x=-\frac{28}{15}$

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✏️ SOLUTION STEP

$5x+4y-4=0x-20=12y$

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Consider the first equation. Anything times zero gives zero.

$5x+4y-4=0-20$

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Subtract 20 from 0 to get −20.

$5x+4y-4=-20$

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Add 4 to both sides.

$5x+4y=-20+4$

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Add −20 and 4 to get −16.

$5x+4y=-16$

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Consider the second equation. Anything times zero gives zero.

$0-20=12y$

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Subtract 20 from 0 to get −20.

$-20=12y$

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Add 4 to both sides.

5x+4y=−20+4

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Swap sides so that all variable terms are on the left hand side.

$12y=-20$

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Divide both sides by 12

$y=\frac{-20}{12}$

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Reduce the fraction $\frac{-20}{12}$ to lowest terms by extracting and canceling out 4.

$y=-\frac{5}{3}$

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Consider the first equation. Insert the known values of variables into the equation.

$5x+4(-\frac{5}{3})=-16$

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Multiply 4 and $-\frac{5}{3}$ to get $-\frac{20}{3}$

$5x-\frac{20}{3} =-16$

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Add $\frac{20}{3}$  to both sides.

$5x=-16+\frac{20}{3}$

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Add −16 and $\frac{20}{3}$ to get $\frac{28}{3}$

$5x=-\frac{28}{3}$

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Divide both sides by 5.

$x=\frac{-\frac{28}{3} }{5}$

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Express $\frac{-\frac{28}{3} }{5}$  as a single fraction.

$x=\frac{-28}{3x5}$

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Multiply 3 and 5 to get 15.

$x=\frac{-28}{15}$

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Fraction $\frac{-28}{15}$  can be rewritten as $-\frac{28}{15}$  by extracting the negative sign.

$x=-\frac{28}{15}$

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The system is now solved.

$x=-\frac{28}{15}$

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[I hope someone learned]