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2 years ago

Solve: X + y = 4 -5x - 6y = -18

Mathematics

2 answers:

OLga [1]2 years ago

7 0

Answer:

x = 6 and y = -2

Step-by-step explanation:

In an equation our aim is to find the value of what we are looking for as well as keeping the equation balanced. For example if we took away 5 only from one side then the equation would change so it's an important rule to keep in mind when solving equations, that you need to keep both sides of the equation the same.

x + y = 4

-5x - 6y = -18

→ We have to multiply the top equation by -6 so the y coefficients are the same

-6x - 6y = -24

-5x - 6y = -18

→ Minus the equations

-x = -6

x = 6

→ Substitute x = 6 back into x + y = 4

6 + y = 4

y = -2

So the solutions are y = -2 and x = 6

LiRa [457]2 years ago

4 0

Answer: x = -5, y = 9

Step-by-step explanation:

The solution to the system of equations can be represented as a point.

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Tan(60)x 20 please hurry!!

lana [24]

Answer:

6.4008

Step-by-step explanation:

7 0

2 years ago

Learning Task 3

ASHA 777 [7]

Answer:

1. The sides are: 38.5, 39.5, 40.5 and 41.5

2. Presently, Inzo is 15 years old and Miz is 10 years old

3. $Distance = 3682km$

4. Possible pairs are: (12, 14), (16, 18) and (20, 24)

5. $L < 38m$

Step-by-step explanation:

The question has lots of missing details. See the comment section for complete question

Solving (a):

Given

Shape: Quadrilateral

Sides: Consecutive

$Perimeter = 160$

Let one of the sides be x. The other sides will be x + 1, x + 2 and x + 3.

So, the perimeter is:

$Perimeter = x + x + 1 + x + 2 + x + 3$

This gives:

$160 = x + x + 1 + x + 2 + x + 3$

Collect Like Terms

$160 -1-2-3= x+x+x+x$

$154= 4x$

Divide both sides by 4

$38.5 = x$

$x =38.5$

So, the sides are: 38.5, 39.5, 40.5 and 41.5

Solving (b):

Given

Presently: $Inzo = 10 + Miz$

Five years ago: $Miz - 5= \frac{1}{3} * (Inzo-5)$ --- (Missing from the question)

Required: Determine their present ages

Substitute $10 + Miz$ for Inzo in the second equation

$Miz - 5 = \frac{1}{3} * (10 + Miz - 5)$

$Miz - 5 = \frac{1}{3} * (Miz + 5)$

Multiply both sides by 3

$3Miz - 15 = Miz + 5$

Collect Like Terms

$3Miz -Miz = 15 + 5$

$2Miz= 20$

Divide both sides by 2

$Miz = 10$

Substitute 10 for Miz in $Inzo = 10 + Miz$

$Inzo = 10 + 5$

$Inzo = 15$

So presently, Inzo is 15 years old and Miz is 10 years old

Solving (3):

Given

Express Train:

$Speed = 100kph$

$Time = t$

Local Train:

$Speed = 45kph$

$Time = t + 45$

Required: Determine the distance between A and B

Distance is calculated as:

$Distance = Speed * Time$

For the express train:

$Distance = 100 * t$

For the local train

$Distance = 45 * (45 + t)$

Distance between both stations are equal; So,

$100 * t = 45 * (45 + t)$

$100 t = 2025 + 45t$

Collect Like Terms

$100 t -45t= 2025$

$55t= 2025$

Divide by 55

$t = 36.82$

Substitute 36.82 for t in $Distance = 100 * t$

$Distance = 100 * 36.82$

$Distance = 3682km$

Solving (4):

Let the even numbers be: n and n + 2.

Sum greater than 24: $n + n + 2 > 24$

Sum less than 60: $n + n + 2 < 60$

So, we have:

$n + n + 2 > 24$

$2n + 2 > 24$

Collect Like Terms

$2n > 24-2$

$2n > 22$

$n > 11$

$n + n + 2 < 60$

$2n + 2< 60$

Collect Like Terms

$2n < 60-2$

$2n < 58$

Divide by 2

$n$

So, we have:

$n > 11$ and $n < 29$

So, possible pairs are: (12, 14), (16, 18) and (20, 24)

Solving (5):

Given

$Perimeter < 152m$

Required: Find the possible lengths

Let the length be L.

Perimeter is calculated as:

$Perimeter =4 * L$

$Perimeter =4 L$

So, we have:

$4L < 152m$

Divide through by 4

$L < 38m$

Hence, length is less than 38m (e.g. 37m)

5 0

2 years ago

What is the vertex of y<∣x−3∣+5

Tcecarenko [31]

Answer:

(3, 5)

Step-by-step explanation:

The graph is is the standard y=|x| except the values tells you that x shifts 3 (within the absolute value or parentheses x does the opposite) to the right and the y value shifts 5 up (numbers outside parentheses affects y and does what it says). You can try using a table of values then graphing to check your answer.

3 0

2 years ago

Explain the difference between simple interest and compound interest.

USPshnik [31]

Simple interest:

Simple interest is simple. Each year, the interest is calculated as a percentage of the principal, as follows: Interest= (principal) x (rate) x (time).

Compound interest:

Compound interest is calculated on the principal amount and also on the accumulated interest of previous periods.

8 0

2 years ago

A new car sells for $25,000. The value of the car decreases by 15% each year. What is the approximate value of the car 5 years a

Deffense [45]

Answer:

A. 25,000 (1 minus 0.15) Superscript 5, or approximately $11,093

Step-by-step explanation:

A. 25,000 (1 minus 0.15) Superscript 5, or approximately $11,093

B. 25,000 minus 1500 (5), or approximately $17,500

C. 25,000 (0.15) Superscript 5, or approximately $18,984

D. 25,000 minus left-bracket (100 minus 15) (5) Right-bracket, or approximately $24,575

Value of the car = $25,000

Percentage decrease per year = 15%

Value after 5 years

Total percentage value of the car = 100%

Percentage value remaining each year = (100% - 15%)

= (1 - 0.15)

Decrease of the car in the next 5 years = $25,000(1 - 0.15)^5

= $25,000(0.85)^5

= $25,000(0.4437053125)

= $11,092.6328125

Approximately = $11.093

Value of the car in the next 5 years = $25,000 - $11,093

= $13,907

7 0

2 years ago

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