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3 years ago

Write an expression that can be used to check the question of 646÷3

Mathematics

1 answer:

steposvetlana [31]3 years ago

5 0

Answer:

the answer × 3

Step-by-step explanation:

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What is the pair of angles called.

vodka [1.7K]

The answer is D. Trust me.

4 0

2 years ago

The vector (a) is a multiple of the vector (2i +3j) and (b) is a multiple of (2i+5j) The sum (a+b) is a multiple of the vector (

kow [346]

Answer:

$\|a\| = 5\sqrt{13}$ .

$\|b\| = 3\sqrt{29}$ .

Step-by-step explanation:

Let $m$ , $n$ , and $k$ be scalars such that:

$\displaystyle a = m\, (2\, \vec{i} + 3\, \vec{j}) = m\, \begin{bmatrix}2 \\ 3\end{bmatrix}$ .

$\displaystyle b = n\, (2\, \vec{i} + 5\, \vec{j}) = n\, \begin{bmatrix}2 \\ 5\end{bmatrix}$ .

$\displaystyle (a + b) = k\, (8\, \vec{i} + 15\, \vec{j}) = k\, \begin{bmatrix}8 \\ 15\end{bmatrix}$ .

The question states that $\| a + b \| = 34$ . In other words:

$k\, \sqrt{8^{2} + 15^{2}} = 34$ .

$k^{2} \, (8^{2} + 15^{2}) = 34^{2}$ .

$289\, k^{2} = 34^{2}$ .

Make use of the fact that $289 = 17^{2}$ whereas $34 = 2 \times 17$ .

$\begin{aligned}17^{2}\, k^{2} &= 34^{2}\\ &= (2 \times 17)^{2} \\ &= 2^{2} \times 17^{2} \end{aligned}$ .

$k^{2} = 2^{2}$ .

The question also states that the scalar multiple here is positive. Hence, $k = 2$ .

Therefore:

$\begin{aligned} (a + b) &= k\, (8\, \vec{i} + 15\, \vec{j}) \\ &= 2\, (8\, \vec{i} + 15\, \vec{j}) \\ &= 16\, \vec{i} + 30\, \vec{j}\\ &= \begin{bmatrix}16 \\ 30 \end{bmatrix}\end{aligned}$ .

$(a + b)$ could also be expressed in terms of $m$ and $n$ :

$\begin{aligned} a + b &= m\, (2\, \vec{i} + 3\, \vec{j}) + n\, (2\, \vec{i} + 5\, \vec{j}) \\ &= (2\, m + 2\, n) \, \vec{i} + (3\, m + 5\, n) \, \vec{j} \end{aligned}$ .

$\begin{aligned} a + b &= m\, \begin{bmatrix}2\\ 3 \end{bmatrix} + n\, \begin{bmatrix} 2\\ 5 \end{bmatrix} \\ &= \begin{bmatrix}2\, m + 2\, n \\ 3\, m + 5\, n\end{bmatrix}\end{aligned}$ .

Equate the two expressions and solve for $m$ and $n$ :

$\begin{cases}2\, m + 2\, n = 16 \\ 3\, m + 5\, n = 30\end{cases}$ .

$\begin{cases}m = 5 \\ n = 3\end{cases}$ .

Hence:

$\begin{aligned} \| a \| &= \| m\, (2\, \vec{i} + 3\, \vec{j})\| \\ &= m\, \| (2\, \vec{i} + 3\, \vec{j}) \| \\ &= 5\, \sqrt{2^{2} + 3^{2}} = 5 \sqrt{13}\end{aligned}$ .

$\begin{aligned} \| b \| &= \| n\, (2\, \vec{i} + 5\, \vec{j})\| \\ &= n\, \| (2\, \vec{i} + 5\, \vec{j}) \| \\ &= 3\, \sqrt{2^{2} + 5^{2}} = 3 \sqrt{29}\end{aligned}$ .

6 0

2 years ago

What number or fractions are between 2/3 and 1 1/3

olganol [36]

To find the fraction inbetween,
1. Add up the 2 fractions
2 Divide it by 2

Step (!) Add them up:
2/3 + 1 1/3 = 2

Step (2) Divide the answer by 2:
2÷ 2 = 1

Answer: The number between 2/3 and 1 1/3 is 1.

5 0

2 years ago

1) Determine the rate of change for the table below: 2) Determine the equation of the line (using slope-intercept form) that int

agasfer [191]

Answer:

b.adot5

Step-by-step explanation:

7 0

2 years ago

A band expects to put 15 songs on their next CD. The band writes and records 60% more songs than they expect to put on the CD.

scoray [572]

Answer: 6

Step-by-step explanation:

From the question, we are informed that a band expects to put 15 songs on their next CD and that the band writes and records 60% more songs than they expect to put on the CD. Therefore, the total songs will be:

= 15 + (60% × 15)

= 15 + (0.6 × 15)

= 15 + 9

= 24 songs.

During the editing process, 75% of the songs are removed. The total number of songs that will be there on the final CD will be:

= 24 - (75% × 24)

= 24 - (0.75 × 24)

= 24 - 18

= 6

6 songs will be there on the final CD.

3 0

2 years ago

Read 2 more answers