$\"\"$

The equation is $\"\"$ 61 = d + ( $\"\"$ 18).

$\"\"$ 61 = d $\"\"$ 18

According to additon property of equality: If a = b, then a + c = b + c.

$\"\"$ 61 + 18 = d $\"\"$ 18 + 18 (Add 18 to each sides)

$\"\"$ 61 + 18 = d (Additive inverse property: $\"\"$ 18 + 18 = 0)

d = $\"\"$ 43 (Add: $\"\"$ 61 + 18 = $\"\"$ 43)

$\"\"$

Check:

To check the solution, substitute d = $\"\"$ 43 in original equation.

$\"\"$ 61 = d $\"\"$ 18 $\"\"$ $\"\"$ 61 = $\"\"$ 43 $\"\"$ 18

$\"\"$ 61 = $\"\"$ 61 (Add: $\"\"$ 43 $\"\"$ 18 = $\"\"$ 61)

Compare the values, the equation is true. The solution is d = $\"\"$ 43.

$\"\"$

The value of d = $\"\"$ 43.