Dac =20 degrees and cab = 40 degrees what is the measure of dab

Dab = dac + cab = 60

In word problems like this, the hardest part is translating the words into math.
First identify the quantities involved.
Let x be “a number”

Next Translate the words.
Translate “three times a number” into “3x”
Translate “the difference between 3x and twelve” into ”3x-12”
Translate “is equal to eight more than x” into “ =8+x”
now string them together:

3x-12 = 8+x