Question

The sum of two numbers is 56. The first number is 2 times greater than the second number. What is the second number?​

Answer 1

Explanation:

Let the numbers be x and y

The sum of the two numbers is 56 :

Step 1:

X + Y = 56.......... (1)

Also, the first number is 2 times greater than the second number:

Step 2:

2X + Y = 0........... (2)

By substitution method, make Y the subject from (2)

Step 3:

Y = -2X .......... (3)

Put (3) into (1)

Step 4

X - 2X = 56

-X = 56

`( - x)/( - 1) = (56)/( - 1)`

X = -56

Put X=56 into (3)

Step 5

`y = - 2( - 56)`

`y = 112`

The second number is now 112.

Answer 2

y = 56/3

Explanation:

We need to write equations to solve

Let the two numbers be x and y

The sum is 56

x+y = 56

The first number is 2 times greater than the second number.

x = 2*y

Substitute this into the first equation

x+y = 56

2y+y=56

3y = 56

y = 56/3