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Solve the system of linear equations below.

4x - 3y = 17
5x + 4y = 60
A.
x = 2, y = -3
B.
x = 5, y = 8
C.
x = 8, y = 5
D.
x = -8, y = -5

Respuesta :

jcherry99

Answer:

x = 8     y = 5

Answer C

Step-by-step explanation:

4x - 3y = 17            Multiply by 4

5x + 4y = 60          Multiply by 3

===========================

(4x - 3y = 17)*4

16x - 12y = 68

(5x + 4y = 60)*3

15x + 12y = 180

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Add the  2 new equations together

16x - 12y = 68

15x + 12y = 180

31x = 248           Divide by 31

31x/31 = 248/31   Divide

x = 8

=================

4*8 - 3y = 17         Substitute 8 for x

32 - 3y   = 17         Subtract 32 from both sides.

32-32 - 3y=17-32  Combine

-3y = - 15               Divide by -3

-3y/-3 = -15/-3

x = 5          

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