linear equations

[bandaidgirl]

solve by substitution method

2x +y = 4

(x +1)^2 + (y-2)^2 = 4


so far i have

y =-2x + 4
(x + 1)^2 + (-2x + 4)^2 =4
(x^2 + 2x +1) + (4x^2 - 8x - 8x + 16) = 4
5x^2 -14x +17 =4
5x^2 - 14x +13= 0


now im lost where do i go from here

 

[yoda]

what happened to the -2 in the 2nd part of the equasion? shouldnt it be (x+1)^2+(-2x+4-2)^2=4?

 

[bandaidgirl]

yes should have 5x^2 - 6x +5 i believe

 

[wjm11]

5x^2 - 6x +5 = 4

5x^2 - 6x + 1 = 0

It's a quadratic equation. Solve by factoring or use the quadratic formula.

 

[Denis]

yes should have 5x^2 - 6x +5 i believe

Noooo....5x^2 - 6x + 1 = 0