Question

if 3+2√5/7-9√5=a+b√5 find a b​

Answer 1

Answer:

a = 3

b = - (61/7)

Step-by-step explanation:

3+  2$\sqrt{5}$/7 -9$\sqrt{5}$  (please type question with correct braces for better understanding)

= (21 + 2$\sqrt{5}$)/7 - 9$\sqrt{5}$

= [(21 + 2$\sqrt{5}$) - 63$\sqrt{5}$] /7

= (21-61$\sqrt{5}$)/7

= (21/7)   -  (61$\sqrt{5}$/7)

= 3 - (61/7)$\sqrt{5}$

if compared with a+b$\sqrt{5}$, we can write,

a = 3

b = - (61/7)