Answer:
B.) 18
Step-by-step explanation:
To find the correct b value we use this formula
b² - 4ac = 0
b = What we are solving for
a = 1
c = 81
b² - 4(1)(81) = 0
b² - 324 = 0
b² = 324

b = ±18
And 18 is one of the answer choices
So B.) 18 is the correct answer.
Answer: -1/9
Step by step explanation:
The common difference of an arithmetic sequence can be found by picking 2 consecutive terms, and subtracting the second from the first. For example, if I chose the terms 2 and 1 8/9, I would find the common difference by:
1 8/9 - 2, which is equal to -1/9.
You can confirm this by picking another pair of consecutive terms. Let's pick 1 7/9 and 1 2/3:
1 2/3 - 1 7/9 = -1/9, as 1 2/3 = 1 6/9, so 1 6/9 - 1 7/9 = -1/9
If you would like to find the value of a in the polynomial, you can do this using the following steps:
(y - 4)(y^2 + 4y + 16) = y^3 + 4y^2 + 16y - 4y^2 - 16y - 64 = y^3 + 4y^2 + ay - 4y^2 - ay - 64
a = 16
The correct result would be 16.
Solution:
1. Move all terms to one side
<span>25{x}^{2}+40x+16-28=0</span>
2. Simplify <span>25{x}^{2}+40x+16-28 to <span>25<span>x<span><span>2</span><span></span></span></span>+40x</span></span><span><span>−12</span></span>
<span>25{x}^{2}+40x-12=0</span>
3. Apply the Quadratic Formula<span>x=\frac{-40+20\sqrt{7}}{50},\frac{-40-20\sqrt{7}}{50}
</span>
4. Simplify solutions
<span>x=-\frac{2(2-\sqrt{7})}{5},-\frac{2(2+\sqrt{7})}{5}</span>
Done!