5x⁴ - 3x³ + 6x) - (3x³ + 11x² - 8x)<span>
</span>Expand the second bracket by multiplying throughout by -1
5x⁴ - 3x³ + 6x - <span>3x³ - 11x² + 8x
</span>
Group like terms and simplify
5x⁴ - 3x³ - 3x³ - 11x² + 6x <span>+ 8x
</span>5x⁴ - 6x³ - <span>11x² + 14x</span>
Just subsitute 8 for n
1/2(8)^2-1/2(8)
1/2(64)-4
32-4
28
D
If you look at the attached graphic, you will see that the altitude (or height) of an equilateral triangle is:
Height = side length * sq root (3) / 2
Area = side^2 * sq root (3) / 4
The answer is the number 1.