Given the following system of equations, type the coefficient matrix. 5x − y = 6 2x + 7y = 9

Question

Given the following system of equations, type the coefficient matrix.

  

5x −  y = 6

2x + 7y = 9

Answer 1

5 -1 6

2 7 9

row 2 = row 2 + row 1 * 7

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37 0 51

x = 51/37

5(51/37) - y = 6

5*51 - 37y = 37*6

255 - 37y = 222

-37y = 222 - 255

y = 33/37

5x −  y = 5(51/37) - (33/37) = 255/37 - 33/37 = 222/37 = 6, so the 1st equation checks

2x + 7y = 2(51/37) + 7(33/37) = 102/37 + 231/37 = 333/37 = 9, so the 2nd equation checks

the OFFICIAL solution is x=51/37 and y=33/37