Answer:
x = 8
x = 7
Step-by-step explanation:
Solving x2-15x+56 = 0 by the Quadratic Formula .
According to the Quadratic Formula, x , the solution for Ax2+Bx+C = 0 , where A, B and C are numbers, often called coefficients, is given by :
- B ± √ B2-4AC
x = ————————
2A
In our case, A = 1
B = -15
C = 56
Accordingly, B2 - 4AC =
225 - 224 =
1
Applying the quadratic formula :
15 ± √ 1
x = —————
2
So now we are looking at:
x = ( 15 ± 1) / 2
Two real solutions:
x =(15+√1)/2= 8.000
or:
x =(15-√1)/2= 7.000
