Y=2x²-3x-2
Y=x-4
Iv already done this using a graph but im getting mixed up rearranging the formular can anybody help?
2007-12-03 23:57:50 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
2x² - 3x - 2 = x - 4
2x² - 4x + 2 = 0
x² - 2x + 1 = 0
(x - 1)(x - 1) = 0
x = 1 (twice)
y = - 3
x = 1 , y = - 3
2007-12-04 00:35:49 · answer #1 · answered by Como 7 · 2⤊ 1⤋
Put y = x - 4 into y = 2x² - 3x - 2, getting:
y = x - 4 = 2x² - 3x - 2 or, transferring every term to one of the sides:
2x² - 3x - 2 - x + 4 = 0 --> 2x² - 4x + 2 = 0. Divide throughout by 2:
x² - 2x + 1= 0 or (x - 1)² = 0. hence x = 1. Put this value of x in either of the equations for y such as in: y = x - 4 = 1 - 4 = - 3. Finally solution is: x = 1, y = - 3.
2007-12-04 08:08:30 · answer #2 · answered by quidwai 4 · 1⤊ 1⤋
Set them equal to each other....
2x^2 - 3x - 2 = x - 4
2x^2 + 2 = 4x
2x^2 - 4x + 2 = 0
(2x - 2) (x - 1)
x = 1 (Single solution)
2007-12-04 08:01:42 · answer #3 · answered by Doctor Q 6 · 1⤊ 0⤋
y = 2x^2 - 3x - 2
y = x - 4
So putting both together,
2x^2 - 3x - 2 = x - 4
2x^2 - 4x + 2 = 0
x^2 - 2x + 1 = 0
(x-1)^2 = 0
x = 1
y = x - 4
y = 1 - 4
y = -3
x = 1, y = -3
2007-12-04 08:03:04 · answer #4 · answered by Tan Z 3 · 1⤊ 0⤋