All categories

3 years ago

What is the solution of 7^3x = 400?

Mathematics

2 answers:

Mazyrski [523]3 years ago

7 0

X= 400/343 simplify each side of the equation and isolate the variable

OlgaM077 [116]3 years ago

6 0

Hi,
$7^{3x}=400\\\\

3x*ln(7)=ln(400)\\\\

x= \dfrac{ln(400)}{3*ln(7)} \\\\

x =1,026334566...
\\x\approx 1.03$

You might be interested in

Radical 8 plus radical 18

maxonik [38]

Answer:

5√2

Step-by-step explanation:

√8 + √18

We first have to find what is the largest perfect square that goes into √8:

4 is the largest, so therefore → √8 gives you 2√2:

Work: √4 * √2 → 2 * √2 → 2√2

Now we have to find what is the largest perfect square that goes into √18:

9 is the largest, so therefore → √18 gives you 3√2:

Work: √9 * √2 → 3 * √2 → 3√2

Because 2√2 and 3√2 have the same "base" of √2, they can be added together:

2√2 + 3√2 = 5√2 (The "bases" are to be left alone!)

7 0

3 years ago

The surface area of a cylinder is increasing at a rate of 9 pi square meters per hour. The height of the cylinder is fixed at 3

Alekssandra [29.7K]

Answer:

$9\pi \text{ cubic meters per hour}$

Step-by-step explanation:

Since, the surface area of a cylinder,

$A= 2\pi r^2 + 2\pi rh$ ................(1)

Where,

r = radius,

h = height,

If $A= 36\pi\text{ square meters}, h = 3\text{ meters}$

$36\pi = 2\pi r^2 + 2\pi r(3)$

$18 = r^2 + 3r$

$\implies r^2 + 3r - 18=0$

$r^2 + 6r - 3r - 18 = 0$ ( by middle term splitting )

$r(r+6)-3(r+6)=0$

$(r-3)(r+6)=0$

By zero product property,

r = 3 or r = - 6 ( not possible )

Thus, radius, r = 3 meters,

Now, differentiating equation (1) with respect to t ( time ),

$\frac{dA}{dt}= 4\pi r\frac{dr}{dt} +2\pi(r\frac{dh}{dt} + h\frac{dr}{dt})$

∵ h = constant, ⇒ dh/dt = 0,

$\frac{dA}{dt} = 4\pi r \frac{dr}{dt} +2\pi h \frac{dr}{dt}$

We have, $\frac{dA}{dt}=9\pi\text{ square meters per hour}, r = h = 3\text{ meters}$

$9\pi = 4\pi (3) \frac{dr}{dt}+2\pi (3)\frac{dr}{dt}$

$9\pi = (12\pi + 6\pi )\frac{dr}{dt}$

$9\pi = 18\pi \frac{dr}{dt}$

$\implies \frac{dr}{dt} =\frac{1}{2}\text{ meter per hour}$

Now,

Volume of a cylinder,

$V=\pi r^2 h$

Differentiating w. r. t. t,

$\frac{dV}{dt}=\pi ( r^2 \frac{dh}{dt}+h(2r)\frac{dr}{dt})=\pi ((3)(6) (\frac{1}{2})) = 9\pi \text{ cubic meters per hour}$

6 0

3 years ago

What is the equation of the line shown in this graph?

san4es73 [151]

Answer:

y=-3

Step-by-step explanation:according to the graph, for all values of x, y is equal to -3, so this function is independent of the variable x, so the equation is y=-3 (constant for all values of the Real numbers)

4 0

3 years ago

Celeste took a taxi. The meter said $45. She tips the driver 15%. How much money did she pay the taxi driver?

mixas84 [53]

Answer:

so I believe we can do 15% of 45, so that is 6.75.

so now we do:

45.00

+ 6.75

51.75 is your answer!

please mark brainliest if correct!

5 0

2 years ago

What's the solution for (9x + 5) - (4x + 3) ?

Vanyuwa [196]

(9x + 5) - (4x+3) = 0
9x - 4x + 5 - 3 = 0
5x + 2 = 0
5x = -2
5x/5 = -2/5
x= -2/5

5 0

3 years ago

Read 2 more answers