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3 years ago

Solve by Substitution Show Steps x = −5y + 4z + 1 x − 2y + 3z = 1 2x + 3y − z = 2

Mathematics

1 answer:

grandymaker [24]3 years ago

7 0

Answer:

(x, y, z) = (1-z, z, z) . . . . . . . an infinite number of solutions

Step-by-step explanation:

Use the first equation to substitute for x in the remaining two equations.

(-5y +4z +1) -2y +3z = 1 . . . . substitute for x in the second equation

-7y +7z = 0 . . . . . . . . . . . . . . simplify, subtract 1

y = z . . . . . . . . . . . . . . . . . . . . divide by -7; add z

2(-5y +4z +1) +3y -z = 2 . . . . substitute for x in the third equation

-7y +7z = 0 . . . . . . . . . . . . . . subtract 2; collect terms

y = z . . . . . . . . . . . . . . . . . . . . divide by -7; add z

<em>This is a dependent set of equations</em>, so has an infinite number of solutions. Effectively, they are ...

x = 1 -z

y = z

z is a "free variable"

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Read 2 more answers

Which of the following describes the translation of the graph of y = x 2 to

VLD [36.1K]

Answer:

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Step-by-step explanation:

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