An angle measures 17 more then 3 time a number. its supplement is three more then seven time the numder. what is the measure of each angle?

If the angles are supplementary angles, that means that they add up to be 180˚.
Angle A is 3x+17 (17 more than 3 times a number) and Angle B is 7x+3 (3 more than 7 times the number).
Both of these added together is equal to 180, so you get: 3x+17+7x+3=180
Combine like terms and get: 10x+20=180
Subtract 20 from both sides: 10x=160
Divide both sides by 10: x=16
Now you have your number.
To find the angles, plug the number back into the statements.
Angle A: 3(16)+17=65˚
Angle B: 7(16)+3=115˚
Check to make sure they add up to equal 180: 65+115=180 √
And you're done!