Question

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x la a 2 = 1

× la a 2 =81

4x la a 2 =1

2x la a 2 =8

3x la a 2 = 75

49x la a 2 = 121

25x la a 2 = 225

36x la a 2 =144

x la a 2 -0,25 =0

2x la a 2 -0,32 = 0

4x la a 2 = 0,04

3x la a 2 =10,8

Answer 1

$\star) {x}^{2} = 1 = > x = \pm \sqrt{1} = \pm \: 1$

$\star) {x}^{2} = 81 = > x = \pm \sqrt{81} = \pm \: 9$

$\star)4 {x}^{2} = 1 \: | \div 4$

${x}^{2} = \frac{1}{4} = > x = \pm \sqrt{ \frac{1}{4} } = \pm \frac{ \sqrt{1} }{ \sqrt{4} } = \pm \: \frac{1}{2}$

$\star)2 {x}^{2} = 8 \: | \div 2$

${x}^{2} = 4 = > x = \pm \sqrt{4} = \pm \: 2$

$\star)3 {x}^{2} = 75 \: | \div 3$

${x}^{2} = 25 = > x = \pm \sqrt{25} = \pm \: 5$

$\star)49 {x}^{2} = 121 \: | \div 49$

${x}^{2} = \frac{121}{49} = > x = \pm \sqrt{ \frac{121}{49} } = \pm \frac{ \sqrt{121} }{ \sqrt{49} } = \pm \: \frac{11}{7}$

$\star)25 {x}^{2} = 225 \: | \div 25$

${x}^{2} = \frac{225}{25} = 9 = > x = \pm \sqrt{9} = \pm \: 3$

$\star)36 {x}^{2} = 144 \: | \div 36$

${x}^{2} = \frac{144}{36} = 4 = > x = \pm \sqrt{4} = \pm \: 2$

$\star) {x}^{2} - 0.25 = 0$

${x}^{2} = 0.25$

${x}^{2} = \frac{25}{100} = \frac{1}{4} = > x = \pm \sqrt{ \frac{1}{4} } = \pm \frac{ \sqrt{1} }{ \sqrt{4} } = \pm \: \frac{1}{2}$

$\star)2 {x}^{2} - 0.32 = 0$

$2 {x}^{2} = 0.32$

$2 {x}^{2} = \frac{32}{100}$

$2 {x}^{2} = \frac{8}{25} \: | \div 2$

${x}^{2} = \frac{ \frac{8}{25} }{2} = \frac{8}{25} \times \frac{1}{2} = \frac{8}{50} = \frac{4}{25}$

$x = \pm \sqrt{ \frac{4}{25} } = \pm \frac{ \sqrt{4} }{ \sqrt{25} } = \pm \: \frac{2}{5}$

$\star)4 {x}^{2} = 0.04$

$4 {x}^{2} = \frac{4}{100}$

$4 {x}^{2} = \frac{1}{25} \: | \div 4$

${x}^{2} = \frac{ \frac{1}{25} }{4} = \frac{1}{25} \times \frac{1}{4} = \frac{1}{100}$

$x = \pm \sqrt{ \frac{1}{100} } = \pm \frac{ \sqrt{1} }{ \sqrt{100} } = \pm \: \frac{1}{10}$

$\star)3 {x}^{2} = 10.8$

$3 {x}^{2} = \frac{108}{10}$

$3 {x}^{2} = \frac{54}{5} \: | \div 3$

${x}^{2} = \frac{ \frac{54}{5} }{3} = \frac{54}{5} \times \frac{1}{3} = \frac{54}{15} = \frac{18}{5}$

$x = \pm \sqrt{ \frac{18}{5} } = \pm \frac{ \sqrt{18} }{ \sqrt{5} } = \pm \: \frac{3 \sqrt{2} \times \sqrt{5} }{5} = \pm \: \frac{3 \sqrt{10} }{5}$