The table shows a direct variation.

Solve the following system by any method -8x-8y=0 -8x+2y=-20

iVinArrow [24]

$\fbox{Solution by using Matrix}$

$\text{Linear Equation} = -8x-8y=0 , -8x+2y=-20$

$\text{Rewrite the linear equations above as a matrix}$

$\left[\begin{array}{ccc}8&-8&0\\-8&2&-20\\\end{array}\right]$

$\text{Apply to Row2 : Row2 + Row1}$

$\left[\begin{array}{ccc}8&-8&0\\-8&-6&-20\\\end{array}\right]$

$\text{ Simplify rows}$

$\left[\begin{array}{ccc}8&-8&0\\0&1&10/3\\\end{array}\right]$

$\text{Note: The matrix is now in echelon form.}$ $\text{The steps below are for back substitution.}$

$\text{Apply to Row1 : Row1 + 8 Row2}$

$\left[\begin{array}{ccc}8&0&80/30\\0&1&10/3\\\end{array}\right]$

$\text{ Simplify rows}$

$\left[\begin{array}{ccc}1&0&10/3\\0&1&10/3\\\end{array}\right]$

$\text{Therefore, the solution is}$

$x= \dfrac{10}{3} \ \text{and} \ \ y=\dfrac{10}{3}$

7 0

3 years ago

Amanda bought new shoes and she received a 25% off discount. If the discount was $17, what was the original price of the shoes?

Ede4ka [16]

Answer:

68

Step-by-step explanation:

6 0

3 years ago

Suppose a car going 65 mph is traveling north parallel to a train going 50 mph. Once the front of the car is as far north as the

scoray [572]

Answer:

0.75 Miles

Step-by-step explanation:

To find the answer we have to find the difference in the distance the train and car travelled

65/60 is 1.083333 which is miles per minute then multiplied by 3 is 3.25 mile gone in 3 minutes

For the train it is 50/60 which is 0.833333 and the times 3 is 2.5 miles in three minutes

3.25 miles minus 2.5 miles is 0.75 miles so that is how long the train is

6 0

3 years ago

Which property is demonstrated by the equation (5 + a) + 3 = (a + 5) + 3?

sineoko [7]

Answer:

Communitive Property

Step-by-step explanation:

Commutative property = 2 + 3 = 3 + 2 or 2(3) = 3(2)

Associative Property = (2 x 3) 5 = 2 (3 x 5) or (2 + 3) + 5 = 2 + (3 + 5)

Inverse Property = 2 + (-2) = 0 or (2/1)(½) = 1

Basic Definitions:

Commutative Property - Gives you the ability to switch the order of the numbers in an expression.

Associative Property - Let's you move the parenthesis in an expression but not the numbers.

Inverse - Uses numbers like 0 and 1.

Using these basic definitions and examples, we can summarize that the best answer would be Communitive Property

4 0

3 years ago

What is 3/8 x 3/8 x 3/8 written as a power

julia-pushkina [17]

Answer:

3/8^3

Step-by-step explanation:

its like 1/2 x 1/2 x1/2 its 1/2^3

or 7x7x7x7x7=7^5 its the same concept....

7 0

1 year ago