Answer:
x = (-1 ± √21) / 2
The first choice
Step-by-step explanation:
x² = 5 - x
Put in standard form
x² + x - 5 = 0
Use quadratic equation
x = ( -b ± √( b² - 4ac) ) / (2a)
Plug in a = 1, b = 1 , c = -5
x = (-1 ± √( 1² - 4*1*(-5)) ) / 2
evaluate
x = (-1 ± √21) / 2
