Evaluate the expression given value of the variables 17

Which matrix equation represents the system of equations? {-x+ 2y = 0 y= -2

Snowcat [4.5K]

We are given a system of equations,

$\begin{cases}-x+2y=0\\y=-2\\ \end{cases}$

This will translate into a 2x2 matrix of coefficients (because 2 equations and 2 unknowns),

$\begin{bmatrix}-1&2\\0&1\\ \end{bmatrix}$

The matrix will then be applied to the vector (lower dimensions on top),

$\begin{bmatrix}x\\y\\ \end{bmatrix}$

And the result vector will be whats on the other side of equals sign,

$\begin{bmatrix}0\\-2\\ \end{bmatrix}$

So to put everything together,

$\begin{bmatrix}-1&2\\0&1\\ \end{bmatrix}\begin{bmatrix}x\\y\\ \end{bmatrix}=\begin{bmatrix}0\\-2\\ \end{bmatrix}$

Hope this helps :)

6 0

3 years ago

Help on this This question plz

mr Goodwill [35]

= -x^2 - (3x - 12x^2 + 7x ) - (2 - 2x - 2)
= -x^2 - 3x + 12x^2 - 7x - 2 + 2x + 2
= 11x^2 - 8x

Answer
11x^2 - 8x

6 0

3 years ago

1. Calculate the area of the circle having the following radius (r) or diameter (d) (π= 3.14) (a) Radius (r) = 3 cm (b) Diameter

Marat540 [252]

The area of circle having radius 3cm is 28.27 cm², diameter 5cm is 19.63 cm², radius 8 ft is 201.06 ft², diameter is 113.1 cm², diameter 20 km is 314.16 km², diameter 15 mm is 176.71 mm² and radius 16 yd is 804.25 yd².

Given the radius and diamtere are (a) Radius (r) = 3 cm (b) Diameter (d) = 5 cm (c) Radius (r) = 8 ft. (d) Diameter (d) = 12 cm (f) Diameter (d) = 20 km (g) Diameter (d) = 15 mm (i) Radius (r) = 16 yd.

We will calculate the area of circle by using the formula A=πr² or π(d/2)².

(a) Radius (r)=3cm

The area of circle is

Area=π(3)²

Area =9π

Here, π=3.14, we get

Area =9×3.14

Area=28.27cm²

(b) Diameter (d)=5cm

The area of circle is

Area=π(5/2)²

Area =π(2.5)²

Area=6.25π

Here, π=3.14, we get

Area =6.25×3.14

Area=19.63cm²

(c) Radius (r)=8 ft

The area of circle is

Area=π(8)²

Area =64π

Here, π=3.14, we get

Area =64×3.14

Area=201.06ft²

(d) Diameter (d)=12cm

The area of circle is

Area=π(12/2)²

Area =36π

Here, π=3.14, we get

Area =36×3.14

Area=113.1cm²

(e) Diameter (d)=20km

The area of circle is

Area=π(20/2)²

Area =100π

Here, π=3.14, we get

Area =100×3.14

Area=314.16km²

(f) Diameter (d)=15mm

The area of circle is

Area=π(15/2)²

Area =56.25π

Here, π=3.14, we get

Area =56.25×3.14

Area=176.71mm²

(g) Radius (r)=16yd

The area of circle is

Area=π(16)²

Area =256π

Here, π=3.14, we get

Area =256×3.14

Area=804.25yd²

Hence, the area of circle having radius and diameter is radius 3cm is 28.27 cm², diameter 5cm is 19.63 cm², radius 8 ft is 201.06 ft², diameter is 113.1 cm², diameter 20 km is 314.16 km², diameter 15 mm is 176.71 mm² and radius 16 yd is 804.25 yd².

Learn more about the area of circle from here brainly.com/question/17096708

#SPJ9

3 0

1 year ago

Let xy=1 and let dy/dt=5 Find dx/dt when x=5

madreJ [45]

So the first step is to take the derivative of xy=1. Don't forget the product chain rule!

 $xy=1
\\x=5
\\y= \frac{1}{x}=\frac{1}{5}
\\ 
\\\frac{dy}{dt}=5
\\
\\x\frac{dy}{dt}+y\frac{dx}{dt}=0
\\
\\5\times5+ \frac{1}{5} \frac{dx}{dt}=0
\\
\\\frac{1}{5} \frac{dx}{dt}=-25
\\
\\ \frac{dx}{dt}=-125
$

3 0

3 years ago

Jose walked to school on 16 of the 20 school days in February. Which

Vadim26 [7]

Answer:

80%

Step-by-step explanation:

Percentage = No. of days he went to school / Total no. of days the school was there * 100

Therefore, it is equal to 16/20 *100

= 16*5

= 80%

7 0

3 years ago

Evaluate the expression given value of the variables 17 - 2c for c = 7