Answer:
8 %
Step-by-step explanation:
To find the percent of trees that are over 30 ft tall, take the number of trees that are over 30 ft tall over the number of tree
Percent = trees over 30 ft tall/ total number of trees
= 6/75
=.08
Change this to a percent by multiply by 100%
.08 * 100%
8 %
Most quadratic functions(which is what you have there, to a degree of 2) are solved using factoring and the zero product law. If you can not factor then you have to use the quadratic formula or graph it. However this one can be factored.
It's pretty simple to just factor it by inspection but I use the chart method, if you know decomposition that works as well.
Factoring gives us,

Then you set each factor to 0 and solve for x,



And the second one,


The solutions to this equation are
x = -1/2, 3
The rate of change is +2
as an ordered pair it would be (1,-3),(2,-1)(3,1),(4,3)