Solve the following simultaneous equations. 2x + 5y = -4. 7x + y = 19

Simultaneous equations have 2 or more unknowns. This simultaneous equation has 2 unknowns, and 2 equations. This simultaneous equation can be solved using elimination or substitution. Substitution involves substituting a value of one of the unknowns into one equation(for example, x=2) from the equation. Then you can find the other unknown (for example, y). The other way to solve this equation, and for this equation the simpler way, is elimination. This involves eliminating one of the unknowns from the equation. This is done by making the coefficient of the unknown the same in both equations. eq1: 2x + 5y = -4eq2: 7x + y = 19By multiplying eq2 by 5, this makes the coefficients of unknown y the same. eq2(*5): 35x +5y = 95Then we can eliminate the y unknown by subtracting eq1 from eq2(*5).35x + 5y = 95-2x + 5y = -4-----------------(35x - 2x) + (5y - 5y) = (95 - -4)33x = 99 x = 3Once we have found x, we substitute this into one of the original equations (eq1 or eq2). 2(3) + 5y = -46 + 5y = -45y = -4 -6 5y = -10y = -2

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