Solve the following quadratic simultaneous equation: y = x + 4 and y = x^2 + 4x
Y = x + 4y = x2 + 4x(as both are equal to y, they can be equated)So: x2 + 4x = x + 4(Rearrange to make the equation equal 0 - subtract x and 4)x2 + 3x - 4 = 0(factorise)(x + 4)(x - 1) = 0Therefore: x = -4 or x = 1(plug these values back into the original equation to find the corresponding values of y)If x = -4, y = - 4 + 4So y = 0If x = 1, y = 1 + 4So y = 5 This means the solutions to these equations are:x = -4 and y = 0x = 1 and y = 5
