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3 years ago

Can someone help me please I don't understand

Mathematics

1 answer:

iVinArrow [24]3 years ago

7 0

The formula for surface area are 2(LW+LH+WH). If the numbers were being placed in the formula, it will become 2[(9*7)+(9*12)+(12*7)]. 9*7 is 63, 9*12 is 108, 12*7 is 84 and the sum will be 255, and multiply by 2 is 510.
The answer is 510

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What is the distance between the following points?

11111nata11111 [884]

Phytagoras Theorem :

c² = a² + b²

c² = 9² + 2²

c² = 81 + 4

c² = 85

c = √85

So, the distance between the following points is √85

Hope it helpful and useful :)

5 0

3 years ago

Show that 1n^ 3 + 2n + 3n ^2 is divisible by 2 and 3 for all positive integers n.

Dmitry_Shevchenko [17]

Prove:

Using mathemetical induction:

P(n) = $n^{3}+2n+3n^{2}$

for n=1

P(n) = $1^{3}+2(1)+3(1)^{2}$ = 6

It is divisible by 2 and 3

Now, for n=k, $n > 0$

P(k) = $k^{3}+2k+3k^{2}$

Assuming P(k) is divisible by 2 and 3:

Now, for n=k+1:

P(k+1) = $(k+1)^{3}+2(k+1)+3(k+1)^{2}$

P(k+1) = $k^{3}+3k^{2}+3k+1+2k+2+3k^{2}+6k+3$

P(k+1) = $P(k)+3(k^{2}+3k+2)$

Since, we assumed that P(k) is divisible by 2 and 3, therefore, P(k+1) is also

divisible by 2 and 3.

Hence, by mathematical induction, P(n) = $n^{3}+2n+3n^{2}$ is divisible by 2 and 3 for all positive integer n.

3 0

2 years ago

Ervin sells vintage cars. Every three months, he manages to sell 13 cars. Assuming he sells cars at a constant rate, what is the

nalin [4]

Answer:

$m=4\frac{1}{3}$

Step-by-step explanation:

the equation to this is

$y=4\frac{1}{3}x$

and slop-intercept form is

$y=mx+b$

with m being the slope,

so,

$m=4\frac{1}{3}$

7 0

2 years ago

Read 2 more answers

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Fynjy0 [20]

Equivalent systems = same line = infinite solutions

5 0

2 years ago

Read 2 more answers

Enter the range of values for x

Pavlova-9 [17]

Greetings from Brasil...

See the attached figure. The smaller the θ angle, the smaller the AB side will be. If the angle θ = 90º, then AB = 25. As θ < 90, then AB < 25

5X - 10 < 25

5X < 25 + 10

X < 35/5

X < 7

The AB side can be neither zero nor negative. So

5X - 10 > 0

5X > 10

X > 10/5

X > 2

8 0

2 years ago