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Without graphing, classify the following system as independent, dependent, or inconsistent -4x-2y=-4 3x-y=68

User Colin Hale
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If you solve both of the equations for y it starts you headed in the direction you need to go. For -4x - 2y = -4. Solving for y we get y = -2x + 2. For the second equation, 3x - y = 68. Solving for y gives you y = 3x - 68. If both the equations are equal to y, then we can set them equal to each other and solve for x. -2x + 2 = 3x - 68. Combining like terms we get 5x = 70 and x = 14. Plugging that x value into one of the equations to solve for y gives us y = 3(14) - 68 and y = -26. That means that there is one point on the graph where those 2 lines cross...at (14, -26). That means that this is an independent consistent system. You don't need to graph to find it.
User SomeTypeFoo
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