<span>18x+9xy is correct all Roots are to x=0 and y=-2
(9x⋅2)+(9x⋅y) is correct </span>Roots are to x=0 and y=-2
From the figure, let the distance of point P from point A on line segment AB be x and let the angle opposite side a be M and the angle opposite side c be N.
Using pythagoras theorem,
![\tan M= \frac{a}{b-x} \\ \\ M=\tan^{-1}\left(\frac{a}{b-x}\right)](https://tex.z-dn.net/?f=%5Ctan%20M%3D%20%5Cfrac%7Ba%7D%7Bb-x%7D%20%5C%5C%20%5C%5C%20M%3D%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7Ba%7D%7Bb-x%7D%5Cright%29)
and
![\tan N= \frac{c}{x} \\ \\ N=\tan^{-1}\left(\frac{c}{x}\right)](https://tex.z-dn.net/?f=%5Ctan%20N%3D%20%5Cfrac%7Bc%7D%7Bx%7D%20%5C%5C%20%5C%5C%20N%3D%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7Bc%7D%7Bx%7D%5Cright%29)
Angle θ is given by
![\theta=180-M-N \\ \\ =180-\tan^{-1}\left(\frac{a}{b-x}\right)-\tan^{-1}\left(\frac{c}{x}\right)](https://tex.z-dn.net/?f=%5Ctheta%3D180-M-N%20%5C%5C%20%20%5C%5C%20%3D180-%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7Ba%7D%7Bb-x%7D%5Cright%29-%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7Bc%7D%7Bx%7D%5Cright%29)
Given that a = 4 units, b = 5 units, and c = 9 units, thus
![\theta=180-\tan^{-1}\left(\frac{4}{5-x}\right)-\tan^{-1}\left(\frac{9}{x}\right)](https://tex.z-dn.net/?f=%5Ctheta%3D180-%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7B4%7D%7B5-x%7D%5Cright%29-%5Ctan%5E%7B-1%7D%5Cleft%28%5Cfrac%7B9%7D%7Bx%7D%5Cright%29)
To maximixe angle θ, the differentiation of <span>θ with respect to x must be equal to zero.
i.e.
![\frac{d\theta}{dx} = -\frac{4}{x^2-10x+41} + \frac{9}{x^2+81} =0 \\ \\ -4(x^2+81)+9(x^2-10x+41)=0 \\ \\ -4x^2-324+9x^2-90x+369=0 \\ \\ 5x^2-90x+45=0 \\ \\ x^2-18x+9=0 \\ \\ x=9\pm6 \sqrt{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bd%5Ctheta%7D%7Bdx%7D%20%3D%20-%5Cfrac%7B4%7D%7Bx%5E2-10x%2B41%7D%20%2B%20%5Cfrac%7B9%7D%7Bx%5E2%2B81%7D%20%3D0%20%5C%5C%20%20%5C%5C%20-4%28x%5E2%2B81%29%2B9%28x%5E2-10x%2B41%29%3D0%20%5C%5C%20%20%5C%5C%20-4x%5E2-324%2B9x%5E2-90x%2B369%3D0%20%5C%5C%20%20%5C%5C%205x%5E2-90x%2B45%3D0%20%5C%5C%20%20%5C%5C%20x%5E2-18x%2B9%3D0%20%5C%5C%20%20%5C%5C%20x%3D9%5Cpm6%20%5Csqrt%7B2%7D%20)
Given that x is a point on line segment AB, this means that x is a positive number less than 5.
Thus
![x=9-6 \sqrt{2}=0.5147](https://tex.z-dn.net/?f=x%3D9-6%20%5Csqrt%7B2%7D%3D0.5147)
Therefore, The distance from A of point P, so that </span>angle θ is maximum is 0.51 to two decimal places.
Answer:
Step-by-step explanation:
- Number of dimes = d, each d = 10 c
- Number of quarters = q, each q = 25 c
- Total = $2 = 200 c
<u>Equations according the given:</u>
<u>Solve for q by substitution:</u>
- 10(q + 6) + 25q = 200
- 10q + 60 + 25q = 200
- 35q = 140
- q = 140/35
- q = 4
<u>Find the value of d:</u>
Nathaniel has 10 dimes and 4 quarters
Answer: B. (-2, -1)
Step-by-step explanation:
(-2, -1) has a y-coordinate (-1) closer to 0 than the rest of the y-coordinates. And 0 would be turning point in this equation.