Question

Solve x^2—y=—2 —x+y=4 using the elimination method

Answer 1

X² - y = -2  .................. equation 1
-x + y = 4  .................. equation 2      from the y's  we can obtain y - y = 0
the new equation will be
x² - x = 2      to for a quadratic equation make the equation equals to zero
x² - x - 2 = 0
x² - 2x + x - 2 = 0       using factorization method
x(x - 2) + 1(x - 2) = 0
(x + 1)(x - 2) = 0
x + 1=0   and  x - 2=0
x = -1 or 2
 subtitute x= -1 in equation 2                     subtitute x= 2 in equation 2
-(-1) + y = 4                                                  -(2) + y = 4 
1 + y = 4                                                       -2 + y = 4 
y= 4 - 1                                                          y= 4 + 2
y= 3                                                                y= 6

the values of x are -1 and 2 . The values of y are 3 and 6
when x is -1, y is 3
when x is 2, y is 6...