Name: Minti
Question Level: Secondary
Who's Asking: Student

how can you solve for x?

f(x) = -1/4pi(x²) =10x -x²(4-pi)/8

Minti,

I would start by moving all the terms to one side of the equal sign.

-1/4pi(x²) =10x -x²(4-pi)/8
-1/4pi(x²) - 10x + x²(4-pi)/8 = 0

Now I see that there is a common factor of x so I get

x[-1/4pi x - 10 + x(4-pi)/8] = 0

To eliminate the fractions I would multiply both sides by 8 and simplify to get

x[-2pi x - 80 + x(4-pi)] = 0
x[-2pi x - 80 + 4x - pi x] = 0
x[(4 - 3pi) x - 80] = 0

Thus

x = 0 or (4 -3pi) x - 80 = 0, that is
x = 0 or x = 80/(4 - 3pi)

Penny