Explain why the formula A = 1/2 ( bh ) works for finding the area of a triangle

12x + 1 = 25 solve the following equation. then place the correct number in the box provided.

How do you solving the solution of each system using elimination?

Ateacher wanted to buy a chair, a bookshelf, two tables and a desk. she spent $900 for all five items and the chair and the desk combined 70% of her total. if the bookshelf cost $50, how much did each of the tables cost?