How do i do this example 8(10a-4)+5a and 5a-12 are equivalent? is she correct?

Organisms that live in the alpine and taiga biomes have developed unique adaptations that aid in their survival. the douglas-fir is a conifer tree that grows in the taiga biome. it has an average height of about 70 feet, and its wood is an important source of lumber.

Write the product as a trinomial. (x + 2)(x + 3) x2 + 5x + 6 x2 + 6x + 6 x2 + 6x + 5 x2 + 5

25 ! the line of best fit is h = 5a + 86. predict the height at age 16.