The digit in ones place of a number is twice the digit in its tens place. if 9 is added to the number, the digit of the sum of obtained are reverse of those of the number find the number

The answer is 12. The digit 2 is 2 times more than 1, so it matches the first part. 12 + 9 = 21. If you switch the digits of 12 around, you will get 21. So the answer is 12.

21

step-by-step explanation:

answer: (c) m∠qpo + (2x + 16)° = 180°

step-by-step explanation:

the opposite angles of a quadrilateral are supplementary.

so, ∠o + ∠q = 180°   and   ∠p + ∠r = 180°

since ∠r = 2x + 16°, we can use substitution as follows:

∠p + ∠r = 180°

∠p + (2x + 16)° = 180°