Can someone please help me with math.

a brother is 12 years older than his sister. four years ago, the brother was 3 times as old as the sister is now. how old is the

jasenka [17]

Answer:

C. 16

Step-by-step explanation:

Brother - b years now.

Sister - s years now.

A brother is 12 years older than his sister.

b - s = 12

(b - 4) - brother 4 years ago.

Four years ago, the brother was 3 times as old as the sister is now.

b - 4 = 3s

b - s = 12 ----> s = b - 12

b - 4 = 3s

b - 4 = 3(b - 12)

b - 4 = 3b - 36

36 - 4 = 3b - b

32 = 2b

b = 16

6 0

3 years ago

Read 2 more answers

30 POINTS PLEASE HELP!

erik [133]

Answer:

6. 3x^3-7x^2+4x-1

7. -6x^4-2x^2+6x+10

8. 42x^4

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

P and q are integers that are multiple of 5. Which of this

zhuklara [117]

Answer:

we conclude that the only option (a) is true.

Step-by-step explanation:

As we know that the multiples of 5 are the numbers which we get when we multiply by 5.

i.e.

5×1=5

5×2=10

Here, 5 and 10 are multiples of 5.

Let p and q are integers that are multiples of 5.

Let us consider

p=5

q=10

so

p+q=5+10

= 15

A number is divisible by 5 if it ends in 5 or 0.

i.e. 15/5 = 3

so p+q is divisible by 3 as there is no remainder left.

Therefore, option (a) is true.

Checking the other options:

(b) P –q is divisible by 10

As

p=5

q=10

so

p-q=5-10

= -5

Numbers that are divisible by 10 need to be even or divisible by 2 and divisible by 5.

As -5 is not divisible by 2.

So, option b is NOT true.

(c) P +q is divisible by 20

As

p=5

q=10

so

p-q=5+10

= 15

Divisibility rule of 20 implies that the last two digits of the number are either 00 or divisible by 20 .

Therefore, P + q= 20 is not divisible by 20 as we don't get the whole number.

(d) P + q is divisible by 25

As

p=5

q=10

so

p-q=5+10

= 15

p+q=15 is not divisible by 25 as it does not end with 00, 25, 50, or 75.

so, option d is NOT correct.

Therefore, we conclude that the only option (a) is true.

5 0

3 years ago

How do i do disss pls help

masya89 [10]

Number one would be x=4, I hope this helps

8 0

3 years ago

5. In this diagram, lines AC and DE are parallel,

zhannawk [14.2K]

The length of side DE is 3cm

<h2 /><h3>Parallel line</h3>

Since the line AC is equivalent to DE, hence AC = DE

To get the length of DE, we will need to get the length oF AC using the Pythagoras theorem:

Given the following parameters

Hypotenuse = 5

Opposite = 4

Required

Adjacent side

Substitute the given parameters into the formula of Pythagoras theorem.

AC² = 5² - 4²

AC² = 25 - 16

AC² = 9

AC = 3

Hence the length of side DE is 3cm

Learn more on Pythagoras theorem here: brainly.com/question/12306722

8 0

3 years ago