Consider the equations y = |x − 1| and y = 3x + 2. The approximate solution of this system of equations is a.(-0.2, 1.2) b.(0.2, -1.2) c.(0.2, 1.2) d.(-0.2, -1.2)
From the first equation: y^2 = x^2 - 2x + 1 From the second equation: y^2 = 9x^2 + 12x + 4 Subtracting one from the other: 8x^2 + 14x - 3 = 0 Find x, then substitute x into one of the equations to obtain y.
Idk how to do that
@LollyLau
Absolute value means the result must be non-negative. By squaring it we remove the absolute value symbol and replace it with a square instead, which is easier to work with. The equation of order two is solved with the quadratic equation.
I forget how to do quadratic equation :( math used to be my #1 subject and I had a seizure so I forgot everything in life
\[x=\frac{-b \pm\sqrt{b^2-4ac}}{2a}\]
._. I don't understand any of that
Alternatively, you can graph the two equations and read the values of the intersections.
HI!!
ugh :/ I still don't understand
ok forget the quadratic equation
alright that's forgotten
if \(x>1\) then \(|x-1|=x-1\) solve \[x-1=3x+2\] in three steps
I think I solved it backwards cause I got -1.5
\[x-1=3x+2\\ -1=2x+2\\ -3=2x\\ -\frac{3}{2}=x\] but that is not a solution, because we assumed that \(x>1\)and it isn't so now one more step
if \(x<1\) then \(|x-1|=1-x\) solve \[1-x=3x+2\]
let me know what you get
pretty positive I did it totally wrong I got -3.3
add \(x\) to both sides then subtract 2 from both sides, then divide both sides by 4
-.25?
yes
awesome :DD
which for some reason they rounded to \(-.2\)
Someone please help with this last part?
Join our real-time social learning platform and learn together with your friends!