All categories

3 years ago

Solve the system of equations using substitution

Mathematics

1 answer:

Andru [333]3 years ago

7 0

Answer:

x = 136/11 , y = 68/11

Step-by-step explanation:

Solve the following system:

{6 x - y = 68

2 y = x

Hint: | Choose an equation and a variable to solve for.

In the second equation, look to solve for x:

{6 x - y = 68

2 y = x

Hint: | Reverse the equality in 2 y = x in order to isolate x to the left hand side.

2 y = x is equivalent to x = 2 y:

{6 x - y = 68

x = 2 y

Hint: | Perform a substitution.

Substitute x = 2 y into the first equation:

{11 y = 68

x = 2 y

Hint: | Choose an equation and a variable to solve for.

In the first equation, look to solve for y:

{11 y = 68

x = 2 y

Hint: | Solve for y.

Divide both sides by 11:

{y = 68/11

x = 2 y

Hint: | Perform a back substitution.

Substitute y = 68/11 into the second equation:

{y = 68/11

x = 136/11

Hint: | Sort results.

Collect results in alphabetical order:

Answer: {x = 136/11 , y = 68/11

You might be interested in

instead of recording the number 1.25cm of redius of a tube a student recorded 1.23cm find the percentage error correct to 1 deci

DaniilM [7]

This would be:-

2 * 100
-- = 1.6%
125

8 0

3 years ago

A special type of password consists of 3 different letters of the alphabet, and the two different numbers, where each letter and

Phoenix [80]

Answer:

There can be 14,040,000 different passwords

Step-by-step explanation:

Number of permutations to order 3 letters and 2 numbers (total 5)

(AAANN, AANNA,AANAN,...)

= 5! / (3! 2!)

= 120 / (6*2)

= 10

For each permutation, the three distinct (English) letters can be arranged in

26!/(26-3)! = 26!/23! = 26*25*24 = 15600 ways

For each permutation, the two distinct digits can be arranged in

10!/(10-2)! = 10!/8! = 10*9 = 90 ways.

So the total number of distinct passwords is the product of all three permutations,

N = 10 * 15600 * 90 = 14,040,000

7 0

4 years ago

Question 2 (6 points)

alexdok [17]

Answer:

here

Step-by-step explanation:

it is basically a sector , use the area formula i.e.

[(theta)/360]*πr^2

4 0

3 years ago

Q1. a. The value of x is 0.3 correct to 1 decimal place.

Yuki888 [10]

I think it is 3 good luck me saying this then u getting the wrong answer

3 0

3 years ago

Hannah is 2 times her sister’s age. The sum of their ages is no more than 18 years. 1) Write an inequality that can be used to r

svetoff [14.1K]

Answer:

1) $x+2x\leq 18$ .

2) $6$ years

Step-by-step explanation:

Let Hanna's sister be $x$ years old.

Then Hanna will be $2x$ years old.

The sum of their ages will be $x+2x$ years.

The statement "no more than 18" means the sum of their ages is less than or equal to 18.

The required inequality is;

$x+2x\leq 18$ .

The inequality we just found is

$x+2x\leq18$ .

We simplify to get;

$3x\leq 18$ .

we divide both sides by $3$ to get;

$x\leq 6$ .

Therefore the oldest age Hannah's sister can be is $6$ years

3 0

4 years ago