the sum of 3 numbers is 13. the second number is 3 subtracted from 3 times the first. the third number is 4 times the first. what is the number

The value of the first number, x, is 2. The value of the second number, y, is 3. The value of the third number, z, is 8.

x + y + z = 13

y = 3x - 3

z = 4x

Because we have values for y and z, we can plug them into the original equation to find the value of x.

x + 3x - 3 + 4x = 13

Combine like terms.

8x - 3 = 13

Add 3 to both sides.

8x = 16

Divide both sides by 8.

x = 2

The value of x is 2.

Because we have the exact value of x, we can insert this into each x value to find the values of y and z.

y = 3 (2) - 3

y = 3

z = 4 (2)

z = 8

2 + 3 + 8 = 13