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3 years ago

Solve by substitution: 2x-y = -5 -x+-y =10

Mathematics

2 answers:

Elenna [48]3 years ago

6 0

2x-y=-5
-x-y=10
3x=-15
x=-5
-10-y=-5
-y=-5+10
-y=5
y=-5
HOPE I HELPED!!!

vlabodo [156]3 years ago

3 0

{2x-y = -5 => -y=-5-2x /*(-1) y=2x+5
{-x+-y =10

Substitute y in the second equation:

-x-y=10

-x-(2x+5)=10

-x-2x-5=10

-3x-5=10 /+5

-3x=15 /:(-3)

x=-5

y=2x+5=2*(-5)+5=-10+5=-5

y=-5

Solution: (-5; -5)

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Consider the system of equations.

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The solution to the system of equations x + 2y = 1 and -3x-2y = 5 is:

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The given system of equations:

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This can be written in matrix form as shown:

$\left[\begin{array}{ccc}1&2\\-3&-2\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right] = \left[\begin{array}{ccc}1\\5\end{array}\right]$

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The solution to the system of equations x + 2y = 1 and -3x-2y = 5 is:

x = -3, y = 2

Learn more here: brainly.com/question/4428059

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