All categories

2 years ago

What is the answer to this equation 9x-7 = - 7

Mathematics

2 answers:

liq [111]2 years ago

8 0

Answer:

I think the answer is -56

Step-by-step explanation:

sorry if wrong

zaharov [31]2 years ago

8 0

Answer:

$\boxed {x=0}$

Step-by-step explanation:

$9x-7 = - 7$

$\boxed {\sf Add \:7 \:to \:both\: sides}$

$9x-7+7=-7+7$

$9x=0$

$\boxed {\sf Divide \:both\: sides\: by\: 9}$

$\cfrac{9x}{9}=\cfrac{0}{9}$

$x=0$

_____________________

You might be interested in

In ASL, the position in which certain signs are completed indicates

CaHeK987 [17]

Answer:

I am pretty sure it is time of event.

Step-by-step explanation:

3 0

2 years ago

Pre cal/cal master needed

weqwewe [10]

Take x-2 and insert it into 2x^2 + 3x-2 where the x is located
2x^2 + 3x-2
2(x-2)^2 + 3(x-2)-2

Now work out 2(x-2)^2 + 3(x-2)-2 also follow PEMDAS
2(x-2)^2 + 3(x-2)-2
Since (x-2)^2 is an Exponent, lets work with that first and expand (x-2)^2.
(x-2)^2
(x -2)(x-2)
x^2 -4x + 4
Now Multiply that by 2 because we have that in 2(x-2)^2
(x-2)^2 = x^2 -4x + 4
2(x-2)^2 = 2(x^2 -4x + 4)
2(x^2 -4x + 4) = 2x^2 - 8x + 8
2x^2 - 8x + 8

Now that 2(x-2)^2 is done lets move on to 3(x-2).

Use the distributive property and distribute the 3
3(x-2) = 3x - 6

All that is left is the -2

Now lets put it all together
2(x-2)^2 + 3(x-2)-2

2x^2 - 8x + 8 + 3x - 6 - 2

Now combine all our like terms
2x^2 - 8x + 8 + 3x - 6 - 2
Combine: 2x^2 = 2x^2
Combine: -8x + 3x = -5x
Combine: 8 - 6 - 2 = 0

So all we have left is
2x^2 - 5x

5 0

3 years ago

Surface area of a sphere is 615.752 m2, what is the volume of the sphere?

const2013 [10]

the volume (V) of a sphere = $\frac{4}{3}$ πr³

We require to know the radius r to calculate the volume

using surface area of a sphere = 4πr² = 615.752

divide both sides by 4π

r² = $\frac{615.752}{12.56}$ = 49.0248...

take the square root of both sides

r = $\sqrt{49.0248..}$ ≈ 7, hence

V= $\frac{4}{3}$ × π × 7³ = 1436.76 m³ → B

8 0

4 years ago

Given P = x^0.3 y^0.7 is the chicken lay eggs production function, where P is the number of eggs lay, x is the number of workers

lora16 [44]

Answer:

Part A)

$\displaystyle \frac{dy}{dx}=-\frac{3}{7}P^\frac{10}{7}x^{-\frac{10}{7}}$

Part B)

The daily operating cost decreases by about $143 per extra worker.

Step-by-step explanation:

We are given the equation:

$\displaystyle P=x^{\frac{3}{10}}y^{\frac{7}{10}}$

Where P is the number of eggs laid, x is the number of workers, and y is the daily operating budget (assuming in US dollars $).

We want to find dy/dx.

So, let’s find our equation in terms of x. We can raise both sides to 10/7. Hence:

$\displaystyle P^\frac{10}{7}=\Big(x^\frac{3}{10}y^\frac{7}{10}\Big)^\frac{10}{7}$

Simplify:

$\displaystyle P^\frac{10}{7}=x^\frac{3}{7}y$

Divide both sides by the x term to acquire:

$\displaystyle y=P^\frac{10}{7}x^{-\frac{3}{7}}$

Take the derivative of both sides with respect to x:

$\displaystyle \frac{dy}{dx}=\frac{d}{dx}\Big[P^\frac{10}{7}x^{-\frac{3}{7}}\Big]$

Apply power rule. Note that P is simply a constant. Hence:

$\displaystyle \frac{dy}{dx}=P^\frac{10}{7}(-\frac{3}{7})(x^{-\frac{10}{7}})$

Simplify. Hence, our derivative is:

$\displaystyle \frac{dy}{dx}=-\frac{3}{7}P^\frac{10}{7}x^{-\frac{10}{7}}$

Part B)

We want to evaluate the derivative when x is 30 and when y is $10,000.

First, we will need to find P. Our original equations tells us that:

$P=x^{0.3}y^{0.7}$

Hence, at x = 30 and at y = 10,000, P is:

$P=(30)^{0.3}(10000)^{0.7}$

Therefore, for our derivative, we will have:

$\displaystyle \frac{dy}{dx}=-\frac{3}{7}\Big(30^{0.3}(10000^{0.7})\Big)^\frac{10}{7}\Big(30^{-\frac{10}{7}}\Big)$

Use a calculator. So:

$\displaystyle \frac{dy}{dx}=-\frac{1000}{7}=-142.857142...\approx-143$

Our derivative is given by dy/dx. So, it represents the change in the daily operating cost over the change in the number of workers.

So, when there are 30 workers with a daily operating cost of $10,000 producing a total of about 1750 eggs, the daily operating cost decreases by about $143 per extra worker.

5 0

3 years ago

3. What is the radius, in centimeters, of a circle that has a circumference of 16 centimeters?

ludmilkaskok [199]

Answer: 8cm I think-

3 0

3 years ago

Read 2 more answers