Answer: a=5+√5
b=5-√5
Step-by-step explanation:
a=?
b=?
P=20
A=20
P=a*b=20
A=a+b=20
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ab=20
a+b=10
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a=10-b
(10-b)b=20
-b²+10b-20=0
b=-10±√100-80/-2
b=-10±√20/-2
b=-10±2√5/-2
b=-10-2√5/-2=5+√55
b=5-√5
a+b=10
a+5-√5=10
a=5+√5
a+5+√5=10
a=5-√5