Answer number 6 please

Which equation and solution can be used to solve this problem? thirteen less than a number is sixteen. 13-n=16: add 13 to both sides. the answer is 29. n+13=16: subtract 13 from both sides. the answer is 3. n+16=13 subtract 13 from both sides. the answer is 3. n-13=16: add 13 to both sides. the answer is 29.

Find the value of x for which the lines are parallel.

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?