1. A plant costs $p$ dollars and a bush costs $b$ dollars.
Ana buys 2 plants and 4 bushes for $42.
Paola buys 7 plants and 9 bushes for $107.

Write down a pair of simultaneous equations and solve them to find the value of $p$ and the value of $b$.
You must show all your working.

$p=.................................................\;b=.................................................$