Question

System of linear equations. 2x + 4y =, 10 2x + 2y + 3z = 3 -3x + y + 2z = -3

Answer 1

Answer:

x = 1, y = 2, z = -1

Step-by-step explanation:

2x + 4y = 10

2x = -4y + 10

x = -2y + 5

now sub -2y + 5 in for x, back into the other 2 equations

2x + 2y + 3z = 3                                   -3x + y + 2z = -3

2(-2y + 5) + 2y + 3z = 3                       -3(-2y + 5) + y + 2z = -3

-4y + 10 + 2y + 3z = 3                           6y - 15 + y + 2z = -3

-2y + 3z = 3 - 10                                    7y + 2z = - 3 + 15

-2y + 3z = - 7                                         7y + 2z = 12

-2y + 3z = -7....multiply by 2

7y + 2z = 12...multiply by -3

--------------------------

-4y + 6z = -14 (result of multiplying by 2)

-21y - 6z = -36 (result of multiplying by -3)

---------------------------add

-25y = - 50

y = -50/-25

y = 2 <===

2x + 4y = 10                        2x + 2y + 3z = 3

2x + 4(2) = 10                      2(1) + 2(2) + 3z = 3

2x + 8 = 10                          2 + 4 + 3z = 3

2x = 10 - 8                            6 + 3z = 3

2x = 2                                   3z = 3 - 6

x = 2/2                                 3z = -3

x = 1  <==                              z = -3/3

                                            z = -1 <===