Answer:
D. 8
Explanation:
To create a trinomial square on the left side of the equation, find a value that is equal to the square of half of b.
(b/2) ² = (-8)²
Add the term to each side of the equation.
x² - 16x + (-8)² = 23 + (-8)²
Simplify the equation.
Raise -8 to the power of 2.
x² - 16x + 64 = 23 + (-8)²
Simplify 23 - (-8)²
Raise - 8 to the power of 2.
x² - 16x + 64 = 23 + 64
Add 23 and 64
x² - 16x + 64 = 87
Factor the perfect trinomial square into (x-8)²
(x-8)²=87
Solve the equation for x.
Take the square root of each side of the equation to set up the solution for x.
(x-8)²*¹/₂ = ±√87
Remove the perfect root factor x-8 under the radical to solve for x.
x - 8 = ±√87
Remove parentheses.
x - 8 = ±√87
Add 8 to both sides of the equation.
x = ±√87 + 8
The result can be shown in multiple forms.
Exact Form:
x = ±√87 + 8
Decimal Form:
x=17.32737905…,−1.32737905…