Question

alguem sabe sobre as duas perguntas ? agradeço deis de já ​

Answer 1

Resposta:

5)

A = (x+1)*(y-2) =50

p=2*(x+1+y-2)=30 ==>x+y-1=15 ==>x=16-y

(16-y+1)*(y-2)=50

(17-y)(y-2)=50

17y-34-y²+2y=50

y²-19y+84=0

y'=[19+√(361  -336)]/2   =(19+5)/2 =12

y''=[19-√(361  -336)]/2   =(19-5)/2 =7

Se y=12  ==>x=16-12=4

Se y=7  ==>x=16-7 =9

Resposta: (4,12) ; (9,7)

6)

2*(x+y)=26 ==>x+y=13

A=x*y=40 ==> y=40/x

x+40/x=13

x²+40=13x

x²-13x+40=0

x'=[13+√(169-160)]/2 =(13+3)/2=8

x''=[13-√(169-160)]/2 =(13-3)/2=5

Se x=8 ==>y=40/x=40/8=5

Se x=5 ==>y=40/5 = 8

Dimensões 6 x 8  em cm