-x - 5y - 5z = 2 4x - 5y + 4z = 19 x + 5y - z = -20 or -x - 5y + z = 17 -5x - 5y + 5z = 5 2x + 5y - 3z = -10
in Algebra 2 Answers by

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.

1 Answer

Let -x - 5y - 5z = 2 be ( Eq. 1 ), 4x - 5y + 4z = 19 be ( Eq. 2 ) and x + 5y - z = -20 be ( Eq. 3 ).

Add ( Eq. 1 ) and ( Eq. 2 ) to eliminate x and y, that is:

- 6z = - 18

z = 3

Substract ( Eq. 1 ) and ( Eq. 2 ) to get ( 4 ) and to eliminate y, and that is:

- 5x - 9z = - 17 ( 4 )

Substitute the value of z to ( Eq. 4 ), that is:

- 5x - 9 ( 3 ) = - 17

- 5x = 10

x = - 2

Substitute the value of x and z to ( Eq. 1 ) to get the value of y, and that is:

4 ( - 2 ) - 5y + 4 ( 3 ) = 19

- 8 - 5y + 12 = 19

- 5y = 15

y = - 3

Thus, the value of x, y, and z is 2, - 3, and 3, respectively.

by

Related questions

Welcome to MathHomeworkAnswers.org, where students, teachers and math enthusiasts can ask and answer any math question. Get help and answers to any math problem including algebra, trigonometry, geometry, calculus, trigonometry, fractions, solving expression, simplifying expressions and more. Get answers to math questions. Help is always 100% free!
83,026 questions
87,739 answers
1,969 comments
4,545 users