You can use this to help you. label the triangle like the picture and use the equations. I hope this helps.
An ecosystem is a geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble of life.
So... hmmm if you check the first picture below, for 2)
we could use the proportions of those small, medium and large similar triangles like

now.. for 3) will be the second picture below
Answer:
27(less than symbol) 5x+7
Step-by-step explanation:
5 times a number is 5x
increase means add