To complete the square you halve the coefficient of the x term and square it. Half of 14 is 7 and 7² is 49. So we add 49 and subtract 49, which means we are not changing the value of the quadratic. So we have x²+14x+49-49+2. This can be written: (x²+14x+49)-49+2, which is (x+7)²-47, which is answer a.
I hope this helps you
a=4
b=9
c= -1
disctirminant =b^2-4ac
disctirminant =9^2-4.4. (-1)
disctirminant =97
x1=-9+square root of 97/2.4= -9+square root of 97/8
x2= -9-square root of 97/2.4= -9-square root of 97/8
<span>Which system models the height of the tennis ball and the height of the dog's mouth over time?
Answer: D
</span>What does the t<span>-coordinate of the solution h = -16t2 + 18t + 4.5 and h = -16t2<span> + 21t + 1.5</span> to this system represent?
Answer: C
Your Welcome :)</span>
B. Y = <span>|x| - 2
when moving left or right...meaning moving horizontally.......the number is added inside the parenthesis.
This one is moving up or down ....meaning moving horizontally........so the number is added outside the parenthesis. If it moves up then add(+)..........if it moves down then subtract(-). The formula used for horizontal shifts is, y=lXl + k
.Here k will become negative or remain positive based on the given data.
Now,
It's a horizontal shift, so we can eliminate C and D.
It moves down so we will subtract and therefore we can eliminate A
so the answer is B.
lets check our answer by using the formula
Y = lxl + k
moves 2 units down so our k = (-2)
Y = lxl + (-2) [substitute k]
Y = lxl - 2
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14^2 - 9^2 = a^2
Easy enough
14^2 = 196
9^2 = 81
196 - 81 = 115
The square root of 115 = 10.72
The third side is 10.72km