x2 + 10x + 21 = (x + 3)(x + 7)
(x2+10x+21)/(x+3) = (x+7)
For a start you tell us what the expression equals....
x = -3.27 or -6.73
It is: x2-10x+21 = 0 and the value of x is 3 or 7 when solved
x2 + 10x + 21 = (x + 3)(x + 7)
(x2+10x+21)/(x+3) = (x+7)
x2+10x+21 = (x+3)(x+7)
x2 + 10x = 0 x2 + 10x + 25 = 25 (x + 5)2 = 25 x + 5 = +-5 x1 = 0 x2 =10
x2 + 9 = 10x x2 - 10x + 9 = 0. (x - 9)(x - 1) = 0. Therefore, x = 1 or 9.
For a start you tell us what the expression equals....
x = -3.27 or -6.73
It is: x2-10x+21 = 0 and the value of x is 3 or 7 when solved
Factorising, we obtain, x2 + 10x + 21 = (x + 7)(x + 3). Thus, x2 + 10x + 21 / (x + 3) = x + 7. That's usually easier than dividing it out!
-6
-2-5
Twenty-Five x2 + 10x = 8 x2 + 10x + 25 = 8 + 25 (x + 5)2 = 33