Question

the difference of two ages of two boys x and y is 3 years. And the sum of their ages is 27. Find their ages.

please help me ..

Answer 1

y = 12
x = 15

Answer 2

but how did you get it ? may i know?

Answer 3

Of course! (:
You set up two equations.

Answer 4

1. x + y = 27
2. x - y = 3

Answer 5

These equations efficiently put all the information into a usable format.

Answer 6

With this system of equations, you'd make another equation in the perspective of y.

Answer 7

To do this, you get your first equation (x + y = 27) and subtract y so you get x= 27 - y.

Answer 8

i really hate math ! T.T

Answer 9

Haha well you're in luck! It's my favorite subject (:

Answer 10

Anyways with your new equation (x = 27 - y) you substitute the x in your second equation (x - y = 3
You end up with (27 - y) - y = 3

Answer 11

Good so far?

Answer 12

i got it . thank you so much sis .. :)) Godbless

Answer 13

Aw no problem! All you have to do from this point on is combine the y's, solve for y, and then subtract your answer for y from 27 to get x. HAVE A LOVELY DAY!

Answer 14

but sis about this: A man is 4 times as old as his daughter. four years from now, the sum of their age will be 78. find their present ages.

Answer 15

Alright give me a couple minutes to plan it out on paper

Answer 16

Okay got it. What I started out with was m = 4d (m for man and d for daughter).

Answer 17

What you need to understand is that this^ equation is in the PRESENT.

Answer 18

To find the ages you need to use another equation which is 4 YEARS from now. To do this, you can use this equation.

(4d + 4) + (d + 4) = 78

Answer 19

Basically what you do is combine like terms and get

5d + 8 + 78.

Then subtract 8 and divide 5 and you see that the daughters age is 14. Just multiply 14 by 4 to get the age of her dad and you're done!

Answer 20

5d + 8 = 78* lol woops

Answer 21

thank you so much ! .. I pray for More knowledge and wisdom of you.

Answer 22

No problem love (:

Answer 23

this one, my last question, the sum of 3 consecutive odd integers is 27. what are the numbers?

Answer 24

haha my favorite. Your equation is

n + n + 2 + n + 4 = 27

Answer 25

combine like terms and you get 3n + 6 = 27.

subtract 6

3n = 21.

divide by 3

n = 7

Answer 26

your numbers are 7, 9 and 11

Answer 27

but why n+4?

Answer 28

Okay. Since they are consecutive odd numbers, the easiest way to describe them in an equation in using a 'like term' if that makes any sence.

Answer 29

For example. to decribe 1 + 3 + 5 = 9 using variables, you would do

n + n + 2 + n + 4

Of course using the value of n as the smallest number.

Answer 30

ah. now i know. thanks a lot sis, may God Bless you for helping me :))

Answer 31

Don't mention it (:

Answer 32

bye sis :))

Answer 33

bye c: