How do you solve #2a^2-30a+108=0#?

2 Answers
Jul 30, 2015

Solve #f(x) = 2a^2 - 30a + 108 = 0#

Ans: 6 and 9

Explanation:

#f(x) = 2y = 2(a^2 - 15a + 54) = 0#
#y = a^2 - 15a + 54 = 0#
I use the new Transforming Method. Both roots are positive.
Factor pairs of (54) -> (2, 27)(3, 18)(6, 9). This sum is 15 = -b.
Then, the 2 real roots of y are : 6 and 9

NOTE. To know more about The new Transforming Method for solving quadratic equations, please search into Google, Yahoo or Bing.

Jul 30, 2015

Use the Bhaskara formula to find #x'=9# and #x''=6#.

Explanation:

The Bhaskara formula is: #x=(-b+-sqrt(b^2-4ac))/(2a)#, where a is the number that multiplies #x^2#, b is the number that multiplies #x# and c is the number that doesn't multiply anyone. You should get to the following calculation:
#x=(30+-6)/4#.
There will be two answers. x' is the sum and x'' is the subtraction.