#1 Plug equations 4, 5, 6, and 7 into equation 3
To better combine like terms ... rearange the numbers
combine like terms (y's and constants cancel out)
Divide by 5
Plug this back into equations 5 and 7
#2 Apply concepts of density based on area and volume in modeling ... Mathematically proficient students can apply the mathematics they know to solve problems arising in ... In Grade 3, students used modeling to solve real-world problems involving perimeter of polygons.
#3 D Ira built his model using cross sections that were cut parallel to the base what shape was each cross section