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First, make sure that one set of variables has opposite coefficients. Fill in all the blanks, then press "ok" { (-4) + 5y = 1 -2x - 5y = 11 -x + 5y = 1 y = answer + -2x - 5y = 11 -x + 5y = 1 ( , ) x = = 12 Solve { -2x + 2y = 8 4x - 2y = 6 Answer ( , ) Sometimes, you will have to multiply one of the equations by a number to get one set of "opposite variables." { What should you multiply the second equationby to make the x variable "opposite variables?" 3x - 4y = -1 x - 6y = -5 -6 3 -3 -4 After multiplying the second equation by -3, what does the second equation look like? { 3x - 4y = -1 x - 6y = -5 -3x - 18y = -5 -3x + 18y = -5 -3x + 18y = 15 -3x - 18y = 15 Solve this system. { 3x - 4y = -1 x - 6y = -5 ( , ) { Solve. 3x - y = 11 5x + 3y = 9 ( , ) Sometimes, you must multiply both equations in order to get "opposite variables". Multiply as indicated: 3(-2x + 7y = -8) { 2(3x - 2y = 12) -2x + 7y = -8 3x - 2y = 12 + Solve for y. -6x + 21y = -24 6x - 4y = 24 the x-coordinate is the y-coordinate is Then solve for x. { -3x + 5y = -16 Solve. -5x - 4y = -2 ( , ) { Solve. 6x + 4y = 6 x - 4y = -13 ( , ) Solve. { -2x - 4y = -12 2x + 3y = 9 ( , ) Solve. { ( , ) 2x - y = 6 x + 4y = 12 Is (5, -2) a solution of { 3x + 4y = 7 x - 2y = 9 Yes No ? Is (-1, 3) a solution of Yes No { -4x + 3y = 13 15x + 3y = -6 ? Have a good day! |