Find f(x) of this equation?

f(x) = 35 = x² + 6x + 7

x² + 6x - 28 = 0

It doesn't factor, so use the quadratic formula,

x = [-b ± √(b² - 4ac)]/2a

a = 1, b = 6, and c = -28

x = [-6 ± √(36 + 112)]/2 = (-6 ± √148)/2

So the roots are x = 3.08276253 and x = -9.08276253

Just replace x with 35 and do the arithmetic. 35X35 + 6X35 + 7 = 1225 + 210 + 7 = 1442.

you have to factor your equation using the quadratic equation:

x=-b+ or - the square root of b squared minus 4ac divided by 2a

or

http://www.oncalc.com/wp-content/uploads/2011/02/q...

if you want an easier picture.

a = 1

b = 6

c = 7

so by plugging in and solving you get:

x = -3 - sqrt(2)

x= sqrt(2) - 3