Question

The model show the area (in square units) of parts of rectangles.
Use the models to find the missing values that complete the expression. Explain your reasoning?

Answer 1

Finding the missing value

$\begin{array}{rcl}2.5\mathrm{x}3.75\mathrm{y}& =& (2.5\mathrm{x}+2.5\times 1.5\mathrm{y})\{\because 2.5\times 1.5=3.75\}\\ & =& (2.5\times \mathrm{x}+2.5\times 1.5\mathrm{y})\\ & =& 2.5(\mathrm{x}+1.5\mathrm{y})\{\mathrm{Using}\mathrm{distributive}\mathrm{property}:\mathrm{a}\times \mathrm{b}+\mathrm{a}\times \mathrm{c}=\mathrm{a}\times (\mathrm{b}+\mathrm{c}\left)\right\}\end{array}$

Therefore,