A student who Is 4 feet tall stands beside a tree. The tree has a shadow that is 10 feet long at the same
time that the shadow of the student is 2 feet long. Find the height of the tree.

the function makes a strait line horizontally with no x intercept but a y intercept at 9.

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graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.