Systems of Nonlinear equations: Find the values of x

Question

X² + y² = 5

y = 3x-1

Answer 1

if you plug in y in to the x^2+^2=5 you would get x^2+(3x-1)^2=5. When that is simplified you would get x^2+9x^2-6x+1=5. When you combine like terms you end up getting 10x^2+9x+1=5. Bring the 5 over to get 10x^2+9x+-4=0 and use the quadratic formula to figure out the x values ( quadratic formula( -b+/- sqrt b^2-4ac)/2a)

Answer 2

Why don't you substitute y = 3x-1 into the first equation, solve the resulting quadratic in x, and then check which solutions are valid in both equations?