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I'm having a very hard time finding the solution set for this math problem. The problem is as follows...
What is the solution set that makes the system of equation true?
y = x^2 -4x - 5 y = -2x - 6
Please help!
I do not know what the hook sign between 2 and x in the first equation means, I was never to school and mainly taught myself algebra as my father had had an accident and fractured his spine at the time. The other I can do maybe not very well but gives you an idea y=-2x-6 y + 2x = -6 2x + 6 = - y x +3 = (-y : 2 ) 3 = (-y : 2) - x 3 : x = (- y : 2) : x 3= (-y : 2)
6 = -y y = - 6 Problem solved! I will finally go to sleep now but I will write to you direct soon you can look this up even if there would be a mistake you can see the method.
y = x^2 -4x - 5 ...(1) y = -2x - 6 ...(2)
so place (1) in (2) x^2-4x-5 = -2x-6 x^2 -2x +1 = 0 (x-1)(x-1) = 0 thus x = 1 ---(3)
now substitute back into both equations (remember x^2 should give you a possibility of 2 answers)
so (3) in (1) y = (1)^2 -4(1) -5 = 10
(3) in (2) y = -2(1) - 6 y = -8
so your answers in coordinate form: (1,10) and (1,-8) the geometric interpretation would be that the straight line graph intersects the parabola at these 2 points
y = x^2 - 4x - 5 y = -2x – 6 Substitute second into the first... -2x - 6 = x^2 - 4x - 5 -6 = x^2 - 4x - 5 + 2x 0 = x^2 - 4x - 5 + 2x + 6 Combine it all... 0 = x^2 - 4x + 2x - 5 + 6 0 = x^2 - 2x + 1 Solve that how you want to, but you can factor it to... (x - 1)(x - 1) = 0 Sooo, x = 1 :) It works when you plug it in
y=x2 - 4x - 5 4x + 5 = x2 x + 1 1/4 = x2 : 4 1 1/4 = x2 : 4 - x 5 = x2 - x 5 - x2 = -x x = x2 + 5 x - 5 = x2 x = x2 + 5 x : x2 = 5 : x2 x = 5 Hope I am correct, even if there would be a mistake you see the method