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scoundrel [369]

2 years ago

11

If 3 boys can build 12 model airplanes in a certain length of time, how many planes can 15 boys make in the same length of time

if they work at the same speed?

1 answer:

zubka84 [21]2 years ago

4 0

It would be five times as many planes so 12*5=60 planes

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7x+4y-6z=-73<br> 8x+5y+6z=-59<br> -4x-8y-3z=46<br> y=

Oksanka [162]

Is this all one equation??

5 0

3 years ago

Suppose the circumference of a circle is 3 pi. What is the diameter?

Charra [1.4K]

This was asked already
c=pid or
c=2pir

use first one
c=3pi
3pi=c=pid
3pi=pid
divide by pi
3=d
diameter=3 units

7 0

3 years ago

Read 2 more answers

Solve the following system of equations by Graphing. Label the solution and all intercepts. 4x-2y=8 y=1/2x+2

vovangra [49]

Answer:

The points that intercepts are (4,4) that's what I got. I hope that helps you.

7 0

3 years ago

The prism shown has a volume of 300 m3. A prism has a length of 7.5 meters, width of w, and height of 5 meters. What is the widt

Shalnov [3]

Answer:

6

Step-by-step explanation:

7.5*5=37.5

200/37.5=6

3 0

3 years ago

Read 2 more answers

Help me asap! I will give you marks

Law Incorporation [45]

Recall the binomial theorem.

$(a+b)^n = \displaystyle \sum_{k=0}^n \binom nk a^{n-k} b^k$

1. The binomial expansion of $\left(1+\frac x3\right)^7$ is

$\left(1 + \dfrac x3\right)^7 = \displaystyle\sum_{k=0}^7 \binom 7k 1^{7-k} \left(\frac x3\right)^k = \sum_{k=0}^7 \binom 7k \frac{x^k}{3^k}$

Observe that

$k = 1 \implies \dbinom 71 \left(\dfrac x3\right)^1 = \dfrac73 x$

$k = 2 \implies \dbinom 72 \left(\dfrac x3\right)^2 = \dfrac73 x^2$

When we multiply these by $8-9x$ ,

• $8$ and $\frac73 x^2$ combine to make $\frac{56}3 x^2$

• $-9x$ and $\frac73 x$ combine to make $-\frac{63}3 x^2 = -21x^2$

and the sum of these terms is

$\dfrac{56}3 x^2 - 21x^2 = \boxed{-\dfrac73 x^2}$

2. The binomial expansion is

$\left(2a - \dfrac b2\right)^8 = \displaystyle \sum_{k=0}^8 \binom 8k (2a)^{8-k} \left(-\frac b2\right)^k = \sum_{k=0}^8 \binom 8k 2^{8-2k} a^{8-k} b^k$

We get the $a^6b^2$ term when $k=2$ :

$k=2 \implies \dbinom 82 2^{8-2\cdot2} a^{8-2} b^2 = 28 \cdot2^4 a^6 b^2 = \boxed{448} \, a^6b^2$

6 0

1 year ago