Răspuns:
[tex] {x}^{2} = \frac{320}{5} = 64 \\ x = \sqrt{64 } = 8[/tex]
b
[tex] \frac{4 \times {x}^{2} \times 27 }{3 \times 16} = \frac{ {x}^{2} \times 9 }{4} = \\ 9 {x}^{2} = 4 \\ {x}^{2} = \frac{4}{9} \\ x = \sqrt{ \frac{4}{9} } = \frac{2}{3} [/tex]
d
[tex] {x}^{2} = 45 \times 20 = 900 \\ x = 30[/tex]
c
[tex] {(x - 1 ) }^{2} = \frac{27}{9} \\ \\ x - 1 = \sqrt{ \frac{27}{9} } = \frac{3 \sqrt{3} }{3} \\ x = \frac{3 \sqrt{3} }{3} + 1 \\ [/tex]
e
[tex]8x \times 3x = 14 \times 21 \\ \\ 24x = 294 \\ x = \frac{294}{24} = 12.25[/tex]
f (2m-1)×(2m-1)=27×3=81
2m ^2-2×m×1+1^2=81
2m^2-2m=81-1=80 | ÷2
m^2- m= 40