3) What is the value of n? * 2n

My sister and I each brought a bottle of sunblock to the beach. My bottle had 89ml and my sister’s had 147ml. How much more sunb

mariarad [96]

Answer:

58 more ml

Step-by-step explanation:

147-89=58 ml.

7 0

2 years ago

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· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ =I.

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

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

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

Find the length of the third side. If necessary, round to the nearest tenth.

Shtirlitz [24]

240 bc you need to mulitpy it and ye

5 0

2 years ago

Read 2 more answers

The rectangle below has an area of x^2-7x+10square meters and a width of x - 5 meters. What expression represents the length of

jolli1 [7]

Answer:

L = (x - 2) meters

Step-by-step explanation:

The area of the rectangle = (x² - 7x + 10) m²

The width = (x - 5) m

length = ?

Area of a rectangle = length × width

x² - 7x + 10 = L(x -5)

note L = length

divide both sides by (x-5)

(x² - 7x + 10)/(x - 5) = L

L = x² - 7x + 10 / (x -5)

Factorize x² - 7x + 10

find the numbers you can multiply to give you 10 and also add to give you -7

The numbers are -2 and -5. Therefore,

x² - 2x - 5x + 10 = 0

x(x - 2) - 5(x - 2) = 0

(x-5)(x-2) = 0

Let us go back to our division

L = x² - 7x + 10 / (x -5)

x² - 7x + 10 = (x-5)(x-2)

L = (x-5)(x-2) / (x -5)

L = (x - 2) meters

7 0

2 years ago

Solve the inequalities for x, and match each solution to its number line graph.

marysya [2.9K]

Answer:

14

Step-by-step explanation:

8 0

2 years ago

3) What is the value of n? * 2n - 36