-12r^2+38r-16=0 slve for R?

Answer 1

-12r² + 38r - 16 = 0
6r² - 19r + 8 = 0
we need factors of 48 (6•8) that add up to 19, which are 16 and 3, so

6r² - 3r - 16r + 8 = 0
3r(2r - 1) - 8(2r - 1) = 0
(3r - 8)(2r - 1) = 0
r = 8/3, r = 1/2

Answer 2

-12r^2+38r-16=0 solve for R?
This is a quadratic eqn in R.

Solution - The given eqn is -

-12r^2+38r-16=0 . Divide this eqn by 2
=> 6 R^2 - 19 R + 8 = 0
=> R = [ 19 (+/-) sqrt of { 19 sqred - 4 (6).(8) } ] divided by 2(6)
=> R = [ 19 (+/-) 13 ] divided by 12
=> R = Either (32/12) or (6/12)

=> R = (8/3) and (1/2) ..................... Answer