Question

помогите пожалуйста решить систему уравнений

Answer 1

$left { {{ a^{2}+28+ b^{2}=100 } atop {b=3a}} right.\\ left { {{ a^{2}+(3a) ^{2} =100-28 } atop {b=3a}} right.\\ left { {{ a^{2}+9 a^{2} =72 } atop {b=3a}} right.\\ left { {{10 a^{2}=72 } atop {b=3a}} right.\\ left { {{ a^{2}= frac{36}{5} } atop {b=3a}} right.\\\ left { {{ a_{1}= sqrt{ frac{36}{5} } } atop {b=3a}} right. \\ left { {{a _{1} = frac{6}{ sqrt{5} } } atop {b _{1} = frac{18}{ sqrt{5} } }} right.$
$left { {{ a_{2}=- sqrt{ frac{36}{5} } } atop {b=3a}} right. \\ left { {{ a_{2} =- frac{6}{ sqrt{5} } } atop { b_{2} = =- frac{18}{ sqrt{5} }$

Ответ :
$( frac{6}{ sqrt{5} }; frac{18}{ sqrt{5} }) ,(- frac{6}{ sqrt{5} };- frac{18}{ sqrt{5} } )$

Answer 2

{a²+28+b²=100
{b=3a

a²+28+(3a)²=100

a=6√5/5

a=-6√5/5

b=3*6√5/5

b=3*(-6√5/5)

b=18√5/5
b=-18√5/5

(a₁;b₁)=(6√5/5; 18√5/5)
(a₂;b₂)=(-6√5/5;-18√5/5)

{(6√5/5)²+28+(18√5/5)²=100
{18√5/5=3*6√5/5*1

{(-6∫5/5)²+28+(-18√5/5)²=100
{-18√5/5=3*(-6√5/5)*1

{100=100
{8,04984=8,04984

{100=100
{-8,04984=-8,04984


ОТВЕТ:

(a₁;b₁)=(6√5/5; 18√5/5)
(a₂;b₂)=(-6√5/5;-18√5/5)