2x+5x=56
7x=56
x=8
2*8= 16-AB
5*8=40-BK
A+b=148,5
a*(2/3)=b*(4/5)
a = 148,5 - b
(148,5 - b)*(2/3)=b*(4/5)
148,5*(2/3)=b*(4/5)+b*(2/3)
99=b*(22/15)
b = (15*99)/22 = 67,5
a = 81
<span>b= 67,5</span>
1 1/9 * 3/10 = 10/9 * 3/10 = 3/9 = 1/3
7^(х - 5) = 3^(х - 5)
(7/3)^( х - 5 ) = 1
(7/3)^( х - 5 ) = (7/3)^0
х - 5 = 0
х = 5 + 0
х = 5.