one half of the sum of a number and 3 is equal to 8

Answer 1

The sum of a number, x, and 3 is expressed as x + 3. One half of that sum would be expressed as 1/2·(x + 3). Then, if one half of the sum is equal to 8, we write

1/2·(x + 3) = 8

Multiplying both sides by 2, we get

x + 3 = 16

Subtracting 3 from both sides,

x = 13