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3 years ago

Solve the linear system of equations using the linear combination method. 4x-9y=20 2x-6y=16

Mathematics

1 answer:

maxonik [38]3 years ago

3 0

The solution is (-4,4)

Step-by-step explanation:

Given equations are:

$4x-9y = 20\ \ \ \ Eqn1\\2x-6x = 16\ \ \ \ Eqn2$

In linear combination method, we have to make coefficients of any one variable opposites by multiplying with an integer

So multiplying 2nd equation by -2

$-2(2x-6y=16)\\-4x+6y=-32\ \ \ \ Eqn3$

Adding Equation 1 and Equation 3:

$4x-9y-4x+12y = 20-32\\3y = -12$

Dividing both sides by 3

$\frac{3y}{3} = \frac{-12}{3}\\y = -4$

Putting y=-4 in equation 1

$4x-9(-4) = 20\\4x +36= 20\\4x = 20-36\\4x = -16$

Dividing both sides by 4

$\frac{4x}{4} = \frac{-16}{4}\\x = -4$

Hence,

The solution is (-4,4)

Keywords: Linear combination, linear equations

Learn more about linear combination method at:

#LearnwithBrainly

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Step-by-step explanation:

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3 years ago

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