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3 years ago

Please help me i will mark you brainliesttttttttttttttt

Mathematics

1 answer:

Bad White [126]3 years ago

4 0

Answer:

18.

Step-by-step explanation:

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PLEASE HELP ME I GIVE 5 STARS !

malfutka [58]

Answer:

It's the 2nd option 2*2*3*3*5

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers

Order the following integers from least to greatest 6, 11, 16, -8, -5

posledela

-8,-5, 6, 11, 16: reasoning if the number is a higher negative it makes it less

3 0

3 years ago

What is the length of the shadow cast by a 12-foot lamp post when the angle of elevation of the sun is 60º? (to the nearest tent

elena-s [515]

Answer:

6.9 foot.

Step-by-step explanation:

Given: Length of lamp post= 12-foot.

The angle of elevation of the sun is 60°.

∴ The length of Lamp post, which is opposite is 12-foot.

Now, finding the length of shadow cast by foot lamp.

Length of shadow is adjacent.

∴ We know the formula for $Tan\theta$ = $\frac{Opposite}{adjacent}$

Next, putting the value in the formula.

⇒ $Tan 60° = \frac{12}{adjacent}$

Cross multiplying both side and using the value of Tan 60°

∴ Adjacent= $\frac{12}{\sqrt{3} } = 6.92$ ≅ 6.9 (nearest tenth value)

6.9 is the length of shadow cast by a 12-foot lamp post.

3 0

2 years ago

(Help! If possible can you explain how you got the answer plz and thank u) If the average weight of 10 sacks of soil is 40 lbs.,

defon

Answer:

I think the answer is C but I'm not too sure so if it doesn't sound right don't click it cuz I don't want you get the answer wrong

6 0

2 years ago

Use Cramer Rule to solve the following system: 8x−5y=70 and 9x+7y=3

nlexa [21]

Answer:

$(x,y) = (5,-6)$

Step-by-step explanation:

$\underline{\textbf{Determinant of a matrix.}}\\\\\text{For a}~ 2 \times 2 ~ \text{matrix,}\\\\\begin{vmatrix} a_1&a_2\\b_1&b_2 \end{vmatrix} = a_1b_2 - a_2b_1\\\\\\\text{For a}~ 3 \times 3 ~ \text{matrix,}\\\\\begin{vmatrix} a_1&a_2&a_3\\ b_1&b_2&b_3\\ c_1&c_2&c_3 \end{vmatrix} = a_1\begin{vmatrix} b_2&b_3\\c_2&c_3 \end{vmatrix} - a_2 \begin{vmatrix} b_1&b_3\\c_1&c_3 \end{vmatrix}+ a_3 \begin{vmatrix} b_1&b_2\\c_1&c_2 \end{vmatrix}\\\\\\$

$~~~~~~~~~~~~~~~~~~=a_1(b_2c_3-b_3c_2) -a_2(b_1c_3-b_3c_1) +a_3(b_1c_2-b_2c_1)$

$\underline{\textbf{Cramer's Rule to solve a system of two equations.}}\\\\\text{Consider the system of two equations:}\\\\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~a_1x + b_1 y= c_1\\\\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~a_2x +b_2 y = c_2\\\\\text{Here,}\\\\x = \dfrac{D_x}{D}= \dfrac{\begin{vmatrix} c_1&b_1\\c_2&b_2 \end{vmatrix}}{\begin{vmatrix} a_1&b_1\\a_2&b_2 \end{vmatrix}}\\\\\\ y= \dfrac{D_y}{D}= \dfrac{\begin{vmatrix} a_1&c_1\\a_2&c_2 \end{vmatrix}}{\begin{vmatrix} a_1&b_1\\a_2&b_2 \end{vmatrix}}\\\\$

$\underline{\textbf{Solution:}}\\\\~~~~~~~~~~~~~~~~~~~~~~~8x-5y = 70~~~~~~...(i)\\\\~~~~~~~~~~~~~~~~~~~~~~~9x +7y = 3~~~~~~~...(ii)\\\\\text{Applying Cramer's rule:}\\\\x = \dfrac{D_x}{D}\\\\\\~~=\dfrac{\begin{vmatrix} 70& -5 \\3&7 \end{vmatrix}}{\begin{vmatrix} 8& -5\\ 9& 7\end{vmatrix}}\\\\\\~~=\dfrac{70(7) -(-5)(3)}{(8)(7)-(-5)(9)}\\\\\\~~=\dfrac{490+15}{56+45}\\\\\\~~=\dfrac{505}{101}\\\\\\~~=5$

$y = \dfrac{D_y}{D}\\\\\\~~=\dfrac{\begin{vmatrix} 8& 70 \\9&3 \end{vmatrix}}{\begin{vmatrix} 8& -5\\ 9& 7\end{vmatrix}}\\\\\\~~=\dfrac{(8)(3) -(70)(9)}{(8)(7)-(-5)(9)}\\\\\\~~=\dfrac{24-630}{56+45}\\\\\\~~=-\dfrac{606}{101}\\\\\\~~=-6$

$\textbf{Hence, the solution to the system of equation is}~ (x,y) = (5,-6)$

7 0

1 year ago