How do you factor 16 = 38r - 12r^216=38r12r2?

1 Answer
Aug 7, 2017

2(2r-1)(3r-8)=02(2r1)(3r8)=0

Explanation:

Set it equal to 00
Take out the common factor of 22 first.

12r^2-38r+16 =012r238r+16=0

2(6r^2-19r+8)=02(6r219r+8)=0

Find factors of 6 and 86and8 whose products ADD to -1919

As a hint, we see that 1919 is odd. Therefore the factors of 88 cannot be 2 and 42and4, because their products will be even, so use 1 and 81and8

" "6 and 8 6and8
" "darr" "darr
" "2" "1" "rarr3xx1 = 3 2 1 3×1=3
" "3" "8" "rarr2xx8=ul16
color(white)(wwwwwwwwwwwwwwww)19

The signs in the brackets will both be negative.

2(2r-1)(3r-8)=0

These are the factors which will lead to solutions of:

r = 1/2 and r = 8/3