1)
f=4/5 x b
f+b=27
[tex] \frac{4}{5} b + {}^{5)} b = {}^{5)} 27 \\ \\ \frac{4b}{5} + \frac{5b}{5} = \frac{135}{5} \\ \\ 4b + 5b = 135 \\ 9b = 135 \\ b = 135 \div 9 \\ b = 15[/tex]
[tex]f = \frac{4}{5} \times b \\ f = \frac{4}{5} \times 15 \\ f = \frac{4 \times 15}{5} \\ f = 4 \times 3 \\ f = 12[/tex]
2)
a+b=60
a-b=24
a=24 +b
24+b + b=60
2b=60-24
2b=36
b=36:2
b=18
a=24+b
a=24+18
a=42
…ᘛ⁐̤ᕐᐷ…ᘛ⁐̤ᕐᐷฅ^•ﻌ•^ฅ
