Let a = speed of the plane A, and b = speed of plane B.
(Assume that the net effect of the wind is negligible.)
From the first sentence, the distance between A and B after each travels for 1 hour is a + b miles. From the second sentence, after 45 minutes, or 0.75 hour, the distance between A and B is 200 miles. Plane a has traveled 0.75a, while plane B has traveled 0.75b.
Hence a + b = 0.75a + 0.75b +200
==> 0.25(a + b) = 200.
==> a + b = 800.
Therefore planes A and B are 800 miles apart now.
Answer:
B'(3, 5)
Step-by-step explanation:
Rule for the translation of a point (x, y) by 'h' units left and 'k' units upwards,
(x, y) → (x - h, y + k)
If h = 4 and k = 3,

Following this rule coordinates of the image point of B will be,
B(7, 2) → B'(7 - 4, 2 + 3)
→ B'(3, 5)
Therefore, coordinates of the image point B' will be,
B'(3, 5)
Answer:
Step-by-step explanation:
Perimeter is
P = 2L + 2W. We are given the perimeter as 180 feet, so
180 = 2L + 2W. Solve this for either L or W. I chose W, no reason...
180 - 2L = 2W so
90 - L = W Hold that thought. We'll come back to it in a minute.
Area is
A = LW. We are given the area as 1800 square feet, so
1800 = LW. Sub in 90 - L for W:
1800 = L(90 - L). Distribute to get a quadratic:

Get everything on one side and solve for the length by factoring:

Factor this however you like to factor quadratics, to get the length of
L = 30 and L = 60. First off, the length is longer than the width in general, so if we want to solve for the width, plug in 60 as L in the equation in bold print:
90 - 60 = W and
30 = W
So L = 60 and W = 30
The decimal is about 1.1 and you can’t simplify it
Answer:
n times 5
Step-by-step explanation:
A matrix Anxn of this way is called an upper triangular matrix. It can be proved that the determinant of this kind of matrix is

In this case, it would be 5+5+...+5 (n times) = n times 5
We are going to develop each determinant by the first column taking as pivot points the elements of the diagonal
![det\left[\begin{array}{cccc}5&a_{12}&a_{13}...&a_{1n}\\0&5&a_{23}...&a_{2n}\\...&...&...&...\\0&0&0&5\end{array}\right] =5+det\left[\begin{array}{ccc}5&a_{23}...&a_{2n}\\0&5&a_{3n}\\...&...&...\\0&0&5\end{array}\right]=5+5+...+det\left[\begin{array}{cc}5&a_{n-1,n}\\0&5\end{array}\right]=5+5+...+5+5\;(n\;times)](https://tex.z-dn.net/?f=det%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D5%26a_%7B12%7D%26a_%7B13%7D...%26a_%7B1n%7D%5C%5C0%265%26a_%7B23%7D...%26a_%7B2n%7D%5C%5C...%26...%26...%26...%5C%5C0%260%260%265%5Cend%7Barray%7D%5Cright%5D%20%3D5%2Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%26a_%7B23%7D...%26a_%7B2n%7D%5C%5C0%265%26a_%7B3n%7D%5C%5C...%26...%26...%5C%5C0%260%265%5Cend%7Barray%7D%5Cright%5D%3D5%2B5%2B...%2Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%26a_%7Bn-1%2Cn%7D%5C%5C0%265%5Cend%7Barray%7D%5Cright%5D%3D5%2B5%2B...%2B5%2B5%5C%3B%28n%5C%3Btimes%29)