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kobusy [5.1K]
3 years ago
7

Solve each system by the addition method.

Mathematics
1 answer:
Aneli [31]3 years ago
7 0
-4x + 7y = 9  ⇒ -4x + 7y = 9  ⇒     8x - 14y = -18
2y = -5x - 22 ⇒ -5x - 2y = 22 ⇒ <u>-35x - 14y = 154</u>
                                                               <u>43x</u> = <u>-172</u>
                                                                43       43
                                                                   x = -4
                                                        -4x + 7y = 9
                                                     -4(-4) + 7y = 9
                                                          16 + 7y = 9
                                                        <u>- 16        - 16</u>
                                                                  <u>7y</u> = <u>-7</u>
                                                                   7      7
                                                                    y = -1
                                                              (x, y) = (-4, -1)
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