SOLUTION: Solve by using the quadratic formula. x2 – 15x + 54 = 0

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Question 49480: Solve by using the quadratic formula. x2 – 15x + 54 = 0
Answer by Osran_Shri(18) About Me  (Show Source):
You can put this solution on YOUR website!
x2 – 15x + 54 = 0 -----------> Equation-1
Quadratic formula for ax2 + bx +c = 0 is:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
from Equation-1,
a=1, b= -15, c=54
Substituting the values of a, b and c into above Quadratic formula to get:
x = {-(-15)+- [sqrt((-15)^2 - 4*1*54)]} / (2*1)
x = {15 +- [sqrt( 225 - 216 )]} / 2
x = {15 +- [sqrt(9)]}/2
x= {15+- 3} / 2
Therefore :
x = ( 15 + 3 ) / 2 and (15 - 3) / 2
x = 18/2 and 12 / 2
Answer:
x = 9, 6

Thanks
B.Shridhar