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Advanced Math / Nonlinear equations in one variable and systems of equations in two variables Difficulty: Easy

y=5x+4y=5x+4

y=5x2+4y=5x2+4

Which ordered pair (x,y)x,y is a solution to the given system of equations?

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Explanation

Choice B is correct. The second equation in the given system is y=5x2+4y=5x2+4. Substituting 5x2+45x2+4 for yy in the first equation of the given system yields 5x2+4=5x+45x2+4=5x+4. Subtracting 44 from both sides of this equation yields 5x2=5x5x2=5x. Subtracting 5x5x from both sides of this equation yields 5x25x=05x2-5x=0. Factoring out a common factor of 5x5x from the left-hand side of this equation yields 5x(x1)=05x(x-1)=0. It follows that 5x=05x=0 or x1=0x-1=0. Dividing both sides of the equation 5x=05x=0 by 55 yields x=0x=0. Substituting 0 for x in the equation y=5x+4 yields y=5(0)+4, or y=4. Therefore, a solution to the given system of equations is the ordered pair (0,4).

Choice A is incorrect and may result from conceptual or calculation errors.

Choice C is incorrect and may result from conceptual or calculation errors.

Choice D is incorrect and may result from conceptual or calculation errors.