(3xy2)3 simplified im not sure how to do this

Nadya [2.5K]

I gotchu !! just give me a moment to write it out

4 0

3 years ago

A boat crew rowed 10.5 miles downstream, with the current, in 1.5 hours. the return trip upstream , against the current , covere

alukav5142 [94]

Answer:

The speed of the boat is 5 miles per hours

The speed of the current is 2 miles per hours .

Step-by-step explanation:

Given as :

The distance cover by boat downstream = D = 10.5 miles

The time taken by boat to cover D distance = T = 1.5 hours

The distance cover by boat Upstream = d = 10.5 miles

The time taken by boat to cover d distance = t = 3.5 hours

Let The speed of boat = x mph

Let The speed of current = mph

Now, According to question

∵ Speed = $\dfrac{Distance}{Time}$

<u>For Downstream</u>

x + y = $\dfrac{D}{T}$

Or, x + y = $\dfrac{10.5}{1.5}$

Or, x + y = 7 .......A

<u>For Upstream</u>

x - y = $\dfrac{d}{t}$

Or, x - y = $\dfrac{10.5}{3.5}$

Or, x - y = 3 .......B

Now, Solving eq A and eq B

So, (x + y) + (x - y) = 7 + 3

Or, (x + x) + (y - y) = 10

Or, 2 x + 0 = 10

∴ x = $\dfrac{10}{2}$

i.e x = 5 mph

So, The speed of the boat = x = 5 miles per hours

Put the value of x into eq A

∵ x + y = 7

Or, 5 + y = 7

∴ y = 7 - 5

i.e y = 2 mph

So, The speed of the current = y = 2 miles per hours

Hence, The speed of the boat is 5 miles per hours and The speed of the current is 2 miles per hours . Answer

7 0

3 years ago

Can someone please help on number 20? WILL MARK YOU AS BRAINIEST. (can you also show how you do the problem?) :(

PSYCHO15rus [73]

Answer:

x =(22-√196)/6=(11-7)/3= 1.333

Step-by-step explanation:

(3x2 - 22x) + 24 = 0

The first term is, 3x2 its coefficient is 3 .

The middle term is, -22x its coefficient is -22 .

The last term, "the constant", is +24

Step-1 : Multiply the coefficient of the first term by the constant 3 • 24 = 72

Step-2 : Find two factors of 72 whose sum equals the coefficient of the middle term, which is -22 .

-72 + -1 = -73

-36 + -2 = -38

-24 + -3 = -27

-18 + -4 = -22 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -18 and -4

3x2 - 18x - 4x - 24

Step-4 : Add up the first 2 terms, pulling out like factors :

3x • (x-6)

Add up the last 2 terms, pulling out common factors :

4 • (x-6)

Step-5 : Add up the four terms of step 4 :

(3x-4) • (x-6)

Which is the desired factorization

Equation at the end of step 2:

(x - 6) • (3x - 4) = 0

STEP 3:

Theory - Roots of a product

3.1 A product of several terms equals zero.

When a product of two or more terms equals zero, then at least one of the terms must be zero.

We shall now solve each term = 0 separately

In other words, we are going to solve as many equations as there are terms in the product

Any solution of term = 0 solves product = 0 as well.

5 0

3 years ago

A manufactured product has a length that is normally distributed with a mean of 12 cm. The product will be unusable if the lengt

Sav [38]

Answer:

a) σ = 0,1612

b) P [ 11,75 < X < 12,35] = 0,92,44 or 92,44 %

Step-by-step explanation:

NOTE: I assume the unusable length s 11,5 and less

a) For a normal distribution, the probability of P = 0,01 corresponds to z(score) = -3,1 then:

- 3,1 = ( X - μ₀ ) / σ

- 3,1 = (11,5 - 12 )/ σ

-3,1 = - 0,5 / σ

σ = 0,1612

b) If σ = 0,1612

P [ 11,75 < X < 12,35]

z₁ (score) = ( 11,75 - 12 ) / 0,1612

z₁ = - 0,25/ 0,1612

z₁ = -1,55

From z table P [ 11,75 < X] = 0,0606

z₂ (score) = ( 12,35 - 12) / 0,1612

z₂ = 0,35 / 01612

z₂ = 2,17

From z table P [ X < 12,35] = 0,9850

Finally P [ 11,75 < X < 12,35] = 0,9850 - 0,0606

P [ 11,75 < X < 12,35] = 0,92,44 or 92,44 %

5 0

3 years ago

Find the Nonpermissible replacement for x in this expression 1/-8x

beks73 [17]

The expression is Undefined for x=0, assuming you intend 1/(-8x).

x=0 is "nonpermissible"

4 0

3 years ago