Need Help!! How to find a and b if (a - 6√5)(2 + b√5) = -82?

Answer 1

a second equation would be helpful

Answer 2

Set each () to -82

(a - 6√5)=-82

Then square both sides

(a-6√5)^2=(-82)^2

a^2 -36 x 5 = 6724

Multiply -36 and 5

a^2 - 180 = 6724

Add 180

a^2 = 6904

Then find the square root of both sides

a = 83. 1

Then do the same for b

Answer 3

if you multiply you'll get 2a + ab(sqrt 5) -12(sqrt 5) - 30b = -82.
then ab = 12 (we need to cancel out ab(sqrt 5) and 12(sqrt 5) since we need to eliminate the sqrt 5.
then we'll have
2a - 30b = -82 ------------------>eq.1
ab=12 ------------------------->eq.2
using eq.1

a = 15b -41
so
(15b - 41)b = 12
15b^2 - 41b -12 = 0

solving you'll get
a = 4 and b = 3 // (best) answer

Answer 4

You have one equation and two unknowns (unknowns=variables).

In order to be able to solve you need an equation for each unknown.

So you need another equation in order to do anything.