SOLUTION: Solve for the y value in this system: {5x-y=4 1+y2=2x

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Question 550289: Solve for the y value in this system: {5x-y=4
1+y2=2x
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
{5x-y=4
1+y2=2x
y=5x-4
substitute the value of y in the equation (2)
1+(5x-4)^2=2x
1+25x^2-40x+16=2x
25x^2-42x+17=0
Find the roots of the equation by quadratic formula

a= 25 b= -42 c= 17

b^2-4ac= 1764 - -1700
b^2-4ac= 64 sqrt%28%0964%09%29=
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( 42 + 8 )/ 50
x1= 1 1
x2=( 42 -8 ) / 50
x2= 0.68 2/3
x ( 1, 0.68)
plug the value of x in any equation to get the value of y
5x-y=4
5-y=4
y=1
(1,1)
5*0.68-y=4
3.4-y=4
-0.6
(0.68,0.6)
m.ananth@hotmail.ca