Question

Type the correct answer in each box. Use numerals instead of words.

Consider this quadratic equation.


x^2 + 2x + 7 = 21


The number of positive solutions to this equation is____.


The approximate value of the greatest solution to the equation, rounded to the nearest hundredth, is____.

Answer 1

1 positive solution

2.87.

Explanation:

x^2 + 2x + 7 = 21

x^2 + 2x - 14 = 0

The product of its roots = c/a = -14 so it will have 1 positive solution.

x = -2 +/- sqrt (2^2 - 4*-14) / 2

x = -1 +/- sqrt60/2

= -1 +/- 3.873

GreATest solution is 2.87