b^2/16a^2-49b^2 : b/4a-7b
при а=2/3,b=8/9
Решите пожалуйстаа)

b²/(4a-7b)(4a+7b) * (4a-7b)/b =b²*(4a-7b) /(4a-7b)(4a+7b)*b =b/(4a +7b) =8/9 :(8/3 +56/9) =8/9 : (24+56)/9 =8/9 : 80/9 =8/9 * 9/80 =8*9/9*80 =8/80 =1/10 =0.1