How do you solve the following system?: −12x+5y=−20,3x−2y=1

1 Answer
Leland Adriano Alejandro
Jul 12, 2016

x=−10542 and y=−11928

Explanation:

The given system
−12x+5y=−20 and 3x−2y=1

Let us use the method of substitution

From the second equation 3x−2y=1

x=1+2y3

We use the second in the first equation

−12x+5y=−20

−12(1+2y3)+5y=−20

−(1+2y3)+10y=−40

(1+2y3)−10y=40

1+2y−30y=120

−28y=119

y=−11928
~~~~~~~~~~~~~~~~~~~~~~~

Solve for x

x=1+2(−11928)3

x=28−23884

x=−21084

x=−10542
~~~~~~~~~~~~~~~~~~~~~~

Checking:at x=−10542 and y=−11928

−12x+5y=−20
−12(−10542)+5(−11928)=−20

10584−59528=−20

105−178584=−20

−168084=−20

#-20=-20

Also

3x−2y=1

3(−10542)−2(−11928)=1

−10514+11914=1

1414=1

1=1

Correct ! at x=−10542 and y=−11928

God bless....I hope the explanation is useful.

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