Solve the Simultaneous Equation: 7x + 8y = 32, x - 4y = 8
7x + 8y = 32 (let this be equation [1])x - 4y = 8 (let this be equation [2])
Make x the subject in equation [2] => x = 8 +4y (let this be equation [3])Sub [3] into [1]
7x + 8y = 32 => 7(8 + 4y) +8y = 3256 +28y + 8y = 3236y +56 = 3236y = -24y = -24/36y = -2/3
Sub this value for y into equation [2]x - 4y = 8 => x - 4(-2/3) = 8x + 8/3 = 8x = 8 - 8/3x = 16/3
Put both values for x and y in equation 2 to checkx = 16/3 y = -2/3
x - 4y = 8(16/3) - 4(-2/3) = (16/3) +(8/3) = 24/3 = 8therefore, the solution is correct
BC
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