Question

Simplify 12 root18 - 6 root128 -3 root80 + 8 root45​

Answer 1

12√5 - 12√2

Explanation:

simplify the terms individually

12√18 = 12√3²·2 = 12·3√2=36√2

-6√128 = 6√2·8² = 6·8√2 = -48√2

-3√80 = 3√4²·5 = -12√5

8√45 = 24√5

Then add them.

You could also write as 12(√5-√2), that's a matter of taste.

Answer 2

Explanation:

`12√(18)-6√(128)-3√(80)+8√(45)\\\\ =12√(3*3*2)-6√(8*8*2)-3√(4*4*5)+8√(3*3*5)\\ \\ =12*3√(2)-6*8√(2)-3*4√(5)+8*3√(5)\\\\=36√(2)-48√(2)-12√(5)+24√(5)\\\\=(36-48)√(2)+(-12+24)√(5)\\\\ =-12√(2)+12√(5)`