Solve the simultaneous equations: x^2-y=16 and 2y-4=14x
Equations: (1) x^2-y=16 and (2) 2y-4=14xRearrange (2) to give y:2y-4=14x(+4) 2y=14x+4(/2) y=7x+2call the new equation (3) y=7x+2Put (3) into (1):x^2-(7x+2)=16(expand) x^2-7x-2=16(-16) x^2-7x-18=0(Factorise) (x-9)(x+2)=0so x=9 or x=-2Substitute x values into (3):when x=9:y=7(9)+2y=63+2y=65or when x=-2y=7(-2)+2y=-14+2y=-12So, either x=9 & y=65 or x=-2 & y=-12
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