Question

me ajudem pfvr

b) c.x²-121=0
c)d.3x²-5x=0
d)e.x²-x=0
e)f.9x²-16=0


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Answer 1

Resposta:

b) x²=121

x=

$x = + - \sqrt{121}$

x=+-11

c) 3x² -5x=0

x( 3x-5)=0

3x-5=0 x=0

3x=5

x=-5/3

d) x² -x=0

x(x-1)=0

x-1=0 x=0

x=1

e) 9x²-16=0

9x²=16

$x = + - \sqrt{ \frac{16}{9} }$

$x = + - \frac{4}{3}$

Answer 2

Explicação passo-a-passo:

1) $\sf x^2-121=0$

$\sf x^2=121$

$\sf x=\pm\sqrt{121}$

• $\sf x'=11$

• $\sf x"=-11$

$\sf S=\{-11,11\}$

2) $\sf 3x^2-5x=0$

$\sf x\cdot(3x-5)=0$

• $\sf x'=0$

• $\sf 3x-5=0$

$\sf 3x=5$

$\sf x"=\dfrac{5}{3}$

$\sf S=\left\{0,\dfrac{5}{3}\right\}$

3) $\sf x^2-x=0$

$\sf x\cdot(x-1)=0$

• $\sf x'=0$

• $\sf x-1=0$

$\sf x"=1$

$\sf S=\{0,1\}$

4) $\sf 9x^2-16=0$

$\sf 9x^2=16$

$\sf x^2=\dfrac{16}{9}$

$\sf x=\pm\sqrt{\dfrac{16}{9}}$

• $\sf x'=\dfrac{4}{3}$

• $\sf x"=\dfrac{-4}{3}$

$\sf S=\left\{\dfrac{-4}{3},\dfrac{4}{3}\right\}$