The sum of four times a first number and a second number is 68. If the first number is decreased by twice the second number the result is -1. Find the numbers.

The first number is 15 and the second number is 8.

Step-by-step explanation:

Let us assume,

Given :

Sum of four times a first number and a second number is 68.

⇒ 4x + y = 68

⇒ y = 68-4x

If the first number is decreased by twice the second number the result is -1.

⇒ x - 2y = -1

Substitute y = 68-4x in the above equation.

⇒ x - 2(68-4x) = -1

⇒ x-136+8x = -1

⇒ 9x - 136 = -1

⇒ 9x = -1+136

⇒ x = 135/9

⇒ x = 15

The first number is 15.

The second number is y = 68-4x.

⇒ y = 68 - 4(15)

⇒ y = 68-60

⇒ y = 8

The second number is 8.