All categories

3 years ago

Please Help. 25 points.

Mathematics

1 answer:

vodomira [7]3 years ago

4 0

Answer:

$\boxed{x = 7, y = 9, z = 68}$

Step-by-step explanation:

We must develop three equations in three unknowns.

I will use these three:

$\begin{array}{lrcll}(1) & 8x + 13y +7 & = & 180 & \\(2)& 9x - 7 + 13y +7 & = & 180 & \\(3)& 8x + 5y - 11 + z & = & 180 &\text{We can rearrange these to get:}\\(4)& 8x + 13y & = & 173 &\\(5) & 9x + 13y & = & 180 & \\(6)& 8x + 5y + z & = & 169 & \\(7)& x & = & \mathbf{7} & \text{Subtracted (4) from (5)} \\\end{array}$

$\begin{array}{lrcll}& 8(7) + 13y & = & 173 & \text{Substituted (7) into (4)} \\& 56 + 13y & = & 173 & \text{Simplified} \\& 13y & = & 117 & \text{Subtracted 56 from each side} \\(8)& y & =& \mathbf{9}&\text{Divided each side by 13}\\& 8(7) + 5(9) + z & = & 169 & \text{Substituted (8) and (7) into (6)} \\& 56 + 45 + z& = & 169 & \text{Simplified} \\& 101 + z& = & 169 & \text{Simplified} \\&z& = & \mathbf{68} & \text{Subtracted 101 from each side}\\\end{array}$

$\boxed{\mathbf{ x = 7, y = 9, z = 68}}$

You might be interested in

Use stokes' theorem to evaluate c f · dr where c is oriented counterclockwise as viewed from above. f(x, y, z = xyi + 5zj + 7yk,

Helga [31]

The intersection can be parameterized by

$C:=\mathbf r(t)=\begin{cases}x(t)=6\cos t\\y(t)=6\sin t\\z(t)=5-6\cos t\end{cases}$

with $0\le t$ .

By Stoke's theorem, the integral of $\mathbf f(x,y,z)=xy\,\mathbf i+5z\,\mathbf j+7y\,\mathbf k$ along $C$ is equivalent to

$\displaystyle\int_C\mathbf f(x(t),y(t),z(t))\cdot\mathrm d\mathbf r(t)=\iint_S\nabla\times\mathbf f\,\mathrm dS$

where $S$ is the region bounded by $C$ . The line integral reduces to

$\displaystyle\int_0^{2\pi}(36\sin t\cos t\,\mathbf i+(25-30\cos t)\,\mathbf j+42\sin t\,\mathbf k)\cdot(-6\sin t\,\mathbf i+6\cos t\,\mathbf j+6\sin t\,\mathbf k)\,\mathrm dt$
$=\displaystyle\int_0^{2\pi}(54(\cos3t-\cos t)-30(3\cos2t-5\cos t+3)+(126-126\cos2t)\,\mathrm dt$
$=\displaystyle\int_0^{2\pi}(36+96\cos t-216\cos2t+54\cos3t)\,\mathrm dt$
$=72\pi$

4 0

3 years ago

ILL GIVE BRAINLIESSTTT

Roman55 [17]

Answer:

its "D"

Step-by-step explanation:

i used a graphing calculator

5 0

2 years ago

Max z = 3x1 + 5x2 subject to: 7x1 + 12x2 ≤ 136 3x1 + 5x2 ≤ 36 x1, x2 ≥ 0 and integer find the optimal solution. what is the valu

Reptile [31]

The second constraint is the same as the objective function, so your problem boils down to finding integer solutions to
.. 3x1 +5x2 = 36

There are 3 solutions. They are (x1, x2) = (12, 0), (7, 3), (2, 6)

The value of the objective function there is (obviously) 36.

4 0

3 years ago

There are 50 pennies in a roll. If you have 150 rolls of pennies, how many pennies do you have?

Y_Kistochka [10]

Answer: 7500

Step-by-step explanation:

multiply 150 by 50

8 0

2 years ago

In a small library , there are 5 nonfiction books for every 9 fiction books There are 130 a . How many fiction books are there ?

Mice21 [21]

Answer: 234

Step-by-step explanation:

If there are 130 nonfiction books, then there are 234 fiction books

6 0

3 years ago

Please Help. 25 points. ​

Please Help. 25 points.