Question for math lovers -1

Algebra Level 3

if root of the equation x 2 10 c x 11 d = 0 { x }^{ 2 }-10cx-11d=0 are a,b and those of x 2 10 a x 11 b = 0 { x }^{ 2 }-10ax-11b=0 are c,d then find the value of a+b+c+d (where a,b,c,d are distinct numbers)

1480 1110 1210 1340

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Stanley Zhao
Jul 16, 2014

Use Vieta's formulas. Therefore, a+b = -11d and c+d = -11b. Now, you can figure out that a+b+c+d = -11(d+b). That means the sum must be a multiple of 11. Than you use Vieta's formulas again to find ab = 10c and cd = 10a. d and b are both multiples of ten so that means the sum must be both a multiple of 11 and 10. I got 1210 as my answer.

it's not mentioned that a,b,c,d are integers!!!

Mayank Holmes - 6 years, 11 months ago

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...