Explain why you should record a 1 in the tens column when you regroup in an addition problem.

The regrouping method help to make a sum equation became easier by separating the numbers into 'tens' and 'ones When the total amount of 'ones' has reach 10 or more , you should record a 1 in the tens column to show that the value of 'tens' has increased
Hope this helps. Let me know if you need additional help!

Horizontal change or the change of x

Hello! i hope this
since the cosine is the ratio of the adjacent side to the hypotenuse, you can see that cos 60° = ½. answer. according to the property of cofunctions (topic 3), sin 30° is equal to cos 60°. sin 30° = ½.