All categories

2 years ago

Solve. The answer must be a fraction. Solve by substituting.

Mathematics

1 answer:

maw [93]2 years ago

4 0

Answer: x = -14/5

Step-by-step explanation: We shall begin by expanding the brackets for both sides of the equation

-2/3 (x + 2) = 1/6 (x + 6)

(-2x/3) -4/3 = (x/6) + 1

By collecting like terms we now have

(-2x/3) - (x/6) = 1 + 4/3

(-4x - x)/6 = 7/3

-5x/6 = 7/3

By cross multiplication we now have

-5x (3) = 7 (6)

-15x = 42

x = -(42/15) {simplify further by dividing the RHS by 3}

x = -14/5

Therefore x equals, minus fourteen over five (-14/5)

You might be interested in

Please help quickly.Thanks :)

Klio2033 [76]

Multiply 2x-5y= -21 by 3 to make it 6x-15y= -63
Multiply 3x-3y= -18 by -5 to make it -15x+15y=90

This cancels the y’s out which leaves us with

6x=-63
&
-15x=90

x for 6x=-63 equals - 10.5 so x is - 10.5 and for -15x=90, x= -6

Then you plug in x into any equation you’d like to find y.

Let’s plug in - 10.5 into 6x... equation.

6(- 10.5)-15y=-63

63-15y= -63
-63 -63

-15y=0
y=0 and x= - 10.5. When you plug in this values it makes the equation true!

But the correct answer is the first one north. Sorry if I’m doing too much hahah

If I’m confusing here’s the right answer...

6x-15y= -63
-15x+15y=90

5 0

2 years ago

Suponhamos que temos x casos confirmados de coronavírus e y casos suspeitos. A - Se triplicar os casos confirmados e cair a meta

aleksandr82 [10.1K]

Answer:

[3x + (y/2)]

Step-by-step explanation:

English Translation

Suppose we have x confirmed cases of coronavirus and y suspected cases. A - If the confirmed cases triple and half of the suspects fall, we will have the following expression to represent the total number of cases:

Solution

Number of confirmed cases = x

Number of suspected cases = y

Number of confirmed cases triples and becomes 3x

Half of the suspected cases fall and becomes (y/2)

Total number of cases then becomes

[3x + (y/2)]

In Portugese/Em português

Número de casos confirmados = x

Número de casos suspeitos = y

O número de casos confirmados triplica e se torna 3x

Metade dos casos suspeitos cai e se torna (y / 2)

O número total de casos passa a ser

[3x + (y / 2)]

Hope this Helps!!!

Espero que isto ajude!!!

8 0

2 years ago

According to an article in Marketing News, fewer checks are being written at the grocery store checkout than in the past. To det

alina1380 [7]

Answer:

ooga booga

Step-by-step explanation:

my feet smell like tooga

6 0

2 years ago

4sin²<img src="https://tex.z-dn.net/?f=%5Cfrac%7Bx%7D%7B2%7D" id="TexFormula1" title="\frac{x}{2}" alt="\frac{x}{2}" align="absm

raketka [301]

Answer:

$\displaystyle x=\left \{\frac{2\pi}{3}+2\pi k,\frac{4\pi}{3}+2\pi k, \frac{8\pi}{3}+2\pi k, \frac{10\pi}{3}+2\pi k\right \}k\in \mathbb{Z}$

Step-by-step explanation:

Hi there!

We want to solve for $x$ in:

$4\sin^2(\frac{x}{2})=3$

Since $x$ is in the argument of $\sin^2$ , let's first isolate $\sin^2$ by dividing both sides by 4:

$\displaystyle \sin^2\left(\frac{x}{2}\right)=\frac{3}{4}$

Next, recall that $\sin^2x$ is just shorthand notation for $(\sin x)^2$ . Therefore, take the square root of both sides:

$\displaystyle \sqrt{\sin^2\left(\frac{x}{2}\right)}=\sqrt{\frac{3}{4}},\\\sin\left(\frac{x}{2}\right)=\pm \sqrt{\frac{3}{4}}$

Simplify using $\displaystyle \sqrt{\frac{a}{b}}=\frac{\sqrt{a}}{\sqrt{b}}$ :

$\displaystyle \sin\left(\frac{x}{2}\right)=\pm \sqrt{\frac{3}{4}},\\\sin\left(\frac{x}{2}\right)=\pm \frac{\sqrt{3}}{\sqrt{4}}=\pm \frac{\sqrt{3}}{2}$

Let $\phi = \frac{x}{2}$ .

<h3><u>Case 1 (positive root):</u></h3>

$\displaystyle \sin(\phi)=\frac{\sqrt{3}}{2},\\\phi = \frac{\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\phi =\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z}$

Therefore, we have:

$\displaystyle \frac{x}{2}=\phi = \frac{\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\frac{x}{2}=\phi =\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z},\\\\\begin{cases}x=\boxed{\frac{2\pi}{3}+2\pi k, k\in \mathbb{Z}},\\x=\boxed{\frac{4\pi}{3}+2\pi k , k \in \mathbb{Z}}\end{cases}$

<h3><u>Case 2 (negative root):</u></h3>

$\displaystyle \sin(\phi)=-\frac{\sqrt{3}}{2},\\\phi = \frac{4\pi}{3}+2\pi k, k\in \mathbb{Z}, \\\\\phi =\frac{5\pi}{3}+2\pi k, k\in \mathbb{Z},\\\begin{cases}x=\boxed{\frac{8\pi}{3}+2\pi k, k\in \mathbb{Z}},\\x=\boxed{\frac{10\pi}{3}+2\pi k , k \in \mathbb{Z}}\end{cases}$

8 0

2 years ago

HELP ASAP-The girls’ soccer team won 80% of its games this season. They won 12 games. -The boys’ soccer team won 70% of its game

tia_tia [17]

Answer:

12 and 14

Step-by-step explanation:

15 - 20% = 12

20 - 30% = 14

3 0

2 years ago