Question

I TRIED SO MANY THINGS AND I JUST DO NOT UNDERSTAND WHAT I AM DOING, CAN I PLEASE GET SOME HELP QUICK. ITS SOLVING ALL SOLUTIONS FOR X.
I included a image please someone help I need help with my homework.

Answer 1

$8. \: \: \: \: 2 {x}^{2} + 14 = 22 \\ \\ = > 2 {x}^{2} = 22 - 14 \\ \\ = > 2 {x}^{2} = 8 \\ \\ = > {x}^{2} = \frac{8}{2} \\ \\ = > {x}^{2} = 4 \\ \\ = > x = \underline{+}\sqrt{4} \\ \\ = > \green {\boxed{x = 2\: or \: (-2)}} \\ \\ \\ \\ \\ 9. \: \: \: \: 8 {x}^{2} + 19 = 54 + 3 {x}^{2} \\ \\ = > 8 {x}^{2} - 3 {x}^{2} = 54 - 19 \\ \\ = > 5 {x}^{2} = 35 \\ \\ = > {x}^{2} = \frac{35}{5} \\ \\ = > {x}^{2} = 7 \\ \\ = > x = \underline{ + } \sqrt{7} \\ \\ = > \green{\boxed{ x = \sqrt{7} \: or \: ( - \sqrt{7} )}}$$\\\\\\\\10. \: \: \: 7 {x}^{2} + 12 = 51 - 4 {x}^{2} \\ \\ = > 7 {x}^{2} + 4 {x}^{2} = 51 - 12 \\ \\ = > 11 {x}^{2} = 39 \\ \\ = > {x}^{2} = \frac{39}{11} \\ \\ = > {x} = \underline{+ }\sqrt{ \frac{39}{11} } \\ \\ = > \green{\boxed{ x = \sqrt{ \frac{39}{11} } \: or \: (- \sqrt{ \frac{39}{11} } )}}$