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Cramers rule<br>hurry up plzzz

olya-2409 [2.1K]

Answer:

Answers provided below

Step-by-step explanation:

From the simultaneous linear equation, we have the coefficient matrix as;

(3 4 5)

(2 -1 8)

(5 -2 7)

The x-matrix is Dx is given by;

(18 4 5)

(13 -1 8)

(20 -2 7)

Similarly, the y-matrix Dy is given by;

(3 18 5)

(2 13 8)

(5 -20 7)

Also,the z-matrix Dz is given by;

(3 4 18)

(2 -1 13)

(5 -2 -20)

Determinant of the coefficient matrix from online determinant calculator is;

D = 136

Determinant of the x-matrix from online determinant calculator is; Dx = 92

Determinant of the y-matrix from online determinant calculator is; Dy = 696

Determinant of the z-matrix from online determinant calculator is; Dz = 576

From crammers rule;

x = Dx/D = 92/136

y = Dy/D = 696/136

z = Dz/D = 576/136

6 0

3 years ago

70 hundreds = _____thousands

matrenka [14]

Answer:

7000 im pretty sure if not im sorry

4 0

3 years ago

Read 2 more answers

Show tan(???? − ????) = tan(????)−tan(????) / 1+tan(????) tan(????)<br> .

anyanavicka [17]

Answer:

See the proof below

Step-by-step explanation:

For this case we need to proof the following identity:

$tan(x-y) = \frac{tan(x) -tan(y)}{1+ tan(x) tan(y)}$

We need to begin with the definition of tangent:

$tan (x) =\frac{sin(x)}{cos(x)}$

So we can replace into our formula and we got:

$tan(x-y) = \frac{sin(x-y)}{cos(x-y)}$ (1)

We have the following identities useful for this case:

$sin(a-b) = sin(a) cos(b) - sin(b) cos(a)$

$cos(a-b) = cos(a) cos(b) + sin (a) sin(b)$

If we apply the identities into our equation (1) we got:

$tan(x-y) = \frac{sin(x) cos(y) - sin(y) cos(x)}{sin(x) sin(y) + cos(x) cos(y)}$ (2)

Now we can divide the numerator and denominato from expression (2) by $\frac{1}{cos(x) cos(y)}$ and we got this:

$tan(x-y) = \frac{\frac{sin(x) cos(y)}{cos(x) cos(y)} - \frac{sin(y) cos(x)}{cos(x) cos(y)}}{\frac{sin(x) sin(y)}{cos(x) cos(y)} +\frac{cos(x) cos(y)}{cos(x) cos(y)}}$

And simplifying we got:

$tan(x-y) = \frac{tan(x) -tan(y)}{1+ tan(x) tan(y)}$

And this identity is satisfied for all:

$(x-y) \neq \frac{\pi}{2} +n\pi$

8 0

3 years ago

John is stuck downtown Atlanta and has used is cell phone to order an Uber. The pick up fee is $20 with an additional charge of

Masteriza [31]

Answer:

$25 + (0.25 * 30)

Step-by-step explanation:

Given that :

Cost of Uber :

Pick up fee = $25

Additional charge = 0.25 cent per mile driven

Cost of 30 mile trip :

Pickup fee + (additional charge * number of miles)

$25 + (0.25 * 30)

25 + 7.5

= $32.5

3 0

3 years ago

The distance between the points (1,2) and (x,-1) is 5 units. Find the possible values of x

Mariulka [41]

Answer:

-3,5

Step-by-step explanation:

$d = \sqrt{(x _{2} - x _1) {}^{2} + (y _{2} - y _{1} {} ) {}^{2} }$

$5 = \sqrt{(x - 1) {}^{2} + ( - 1 - 2) {}^{2} }$

$5 = \sqrt{(x - 1) {}^{2} + ( - 3) {}^{2} }$

$25 = (x - 1) {}^{2} + 9$

$16 = (x - 1) {}^{2}$

$4 = x - 1$

$x = 5$

Or

$- 4 = x - 1$

$x = - 3$

7 0

3 years ago