All categories

3 years ago

Pleaseeeeeee help meeeeeeee A boat travels for 4 hours at a constant speed of 35.25 km/h.

Mathematics

1 answer:

Fittoniya [83]3 years ago

8 0

Answer:

141 km

Step-by-step explanation:

This is because as the boat travels at a constant speed, it will travel the same distance each hour. The boat travels at 35.25 km/h, so you must multiply this number by 4.

This gets the answer 141 km.

You might be interested in

Solve for XX. Assume XX is a 2×22×2 matrix and II denotes the 2×22×2 identity matrix. Do not use decimal numbers in your answer.

sveticcg [70]

The question is incomplete. The complete question is as follows:

Solve for X. Assume X is a 2x2 matrix and I denotes the 2x2 identity matrix. Do not use decimal numbers in your answer. If there are fractions, leave them unevaluated.

$\left[\begin{array}{cc}2&8\\-6&-9\end{array}\right]$ · X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ =<em>I</em>.

First, we have to identify the matrix <em>I. </em>As it was said, the matrix is the identiy matrix, which means

<em>I</em> = $\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]$

So, $\left[\begin{array}{cc}2&8\\-6&-9\end{array}\right]$ · X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ = $\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]$

Isolating the X, we have

X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ = $\left[\begin{array}{cc}2&8\\-6&-9\end{array}\right]$ - $\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]$

Resolving:

X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ = $\left[\begin{array}{ccc}2-1&8-0\\-6-0&-9-1\end{array}\right]$

X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ = $\left[\begin{array}{ccc}1&8\\-6&-10\end{array}\right]$

Now, we have a problem similar to A.X=B. To solve it and because we don't divide matrices, we do X=A⁻¹·B. In this case,

X= $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ ⁻¹· $\left[\begin{array}{ccc}1&8\\-6&-10\end{array}\right]$

Now, a matrix with index -1 is called Inverse Matrix and is calculated as: A . A⁻¹ = I.

So,

$\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ · $\left[\begin{array}{ccc}a&b\\c&d\end{array}\right]$ = $\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]$

9a - 3b = 1

7a - 6b = 0

9c - 3d = 0

7c - 6d = 1

Resolving these equations, we have a= $\frac{2}{11}$ ; b= $\frac{7}{33}$ ; c= $\frac{-1}{11}$ and d= $\frac{-3}{11}$ . Substituting:

X= $\left[\begin{array}{ccc}\frac{2}{11} &\frac{-1}{11} \\\frac{7}{33}&\frac{-3}{11} \end{array}\right]$ · $\left[\begin{array}{ccc}1&8\\-6&-10\end{array}\right]$

Multiplying the matrices, we have

X= $\left[\begin{array}{ccc}\frac{8}{11} &\frac{26}{11} \\\frac{39}{11}&\frac{198}{11} \end{array}\right]$

6 0

3 years ago

A taxi service charges $4.50 to pick someone up and then $0.75 per mile during the ride.

Umnica [9.8K]

Part A : y=$0.75m+$4.50
Part B : $8.25

8 0

3 years ago

Use the given information to solve for x and y

Anuta_ua [19.1K]

Answer:

x = 10 and y = 7

Step-by-step explanation:

Equalateral triangle means all sides are equal.

x = 10, easy

make y + 3 = 10

y = 7

Easy, no real math needed. lol

4 0

3 years ago

Can someone please help me to solve this? ASAP<br> Please with explanation, no spam

snow_lady [41]

Answer:

<h2>which question dear..maybe you forgot to add the attachment...</h2>

7 0

4 years ago

NEED MATH HELP NOW. Please solve for x-intercept.

Lelechka [254]

Answer:

(1, 0) and (3, 0)

Step-by-step explanation:

y=2x²-8x+6

x- intercept when y=0

2x²-8x+6=0
x²-4x+4=1
(x-2)²=1
x-2=1 ⇒ x= 3
x-2= -1 ⇒ x= 1

5 0

3 years ago