Do you mean how you can tell between an area formula and a volume formula? Well usually like on a reference sheet it says the shape and the letter a or v, a representing area and v representing volume. I hope this helps, if it doesn't please tell me in the comment section
Answer:
the answer is 7×9=(7×10)-(7×1)
Perpendiculars are any lines that intersect to make or forms a right angle.
Answer:
One interior angle is 50°.
Exterior angle is 95°.
Step-by-step explanation: