We know that in a pair of triangles, if two pairs of corresponding angles are congruent, then the triangles are similar. And if the two angle pairs are similar then the third pair must also be equal.
So, the corresponding sides are also proportional and we can write them as:
the product of five times a number and nine the difference of nine times a number and five the sum of five times a number and five the difference of five times a number and nine
We know that <span>Function 1 shows a greater rate of change, because Maddy spends $20 each month and Caitlin spends $18. </span> Maddy spends 2 dollars more.
Therefore the correct answer is the last option. <span />
