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IrinaVladis [17]
3 years ago
12

Solve these systems of equations Using the elimination method.

Mathematics
2 answers:
grandymaker [24]3 years ago
8 0
A. 3x + y = 13 → 15x + 5y = 65
    x -  5y = 15 →     x -  5y = 15
                                     16x = 80
                                      16     16
                                        x = 5
                                 x - 5y = 15
                                 5 - 5y = 15
                               - 5          - 5
                                     -5y = 10
                                      -5     -5
                                        y = -2
                                 (x, y) = (5, -2)

b.    6x - y = 14
      2x + y = 12
            8x = 26
             8      8
              x = 3¹/₄
       6x - y = 14
6(3¹/₄) - y = 14
   19¹/₂ - y = 14
 - 19¹/₂       - 19¹/₂
             -y = -5¹/₂
             -1      -1
               y = 5¹/₂
        (x, y) = (3¹/₄, 5¹/₂)

c. 3x -  4y = 22 → 15x - 20y = 110
    2x + 5y =   7 →  8x + 20y =   28
                                        23x = 138
                                         23       23
                                            x = 6
                                   3x - 4y = 22
                                3(6) - 4y = 22
                                   18 - 4y = 22
                                 - 18         - 18
                                         -4y = 4
                                          -4    -4
                                            y = -1
                                     (x, y) = (6, -1)
Tanzania [10]3 years ago
8 0
A). 3x + y = 13 
<span>x - 5y = 15 
</span><span>multiplier equation 1 by 5
15x+5y=65
DSA
</span><span>15x+5y=65
</span><span>x - 5y = 15 
</span>remaini<span>ng
16x=80
x=5
5-5y=15
-5y=15-5
-5y=10
y=</span>10 ÷ -5
y=-2
x,y
5,-2
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Answer:

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Step-by-step explanation:

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