Solve each equation using the quadratic formula. \text { 1. } 2 x^{2}-5 x+3=0 \text { 2. } 2 x^{2}-x-13=2 \text { 3. } 2 x^{2}-x-4=2 \text { 4. } 8 x^{2}-4 x=18 \text { 5. } 10 x^{2}+9=x \text { 6. } x^{2}=9 x-20 \text { 7. } 9 x^{2}-11=6 x \text { 8. } 4 x^{2}-8=x \text { 9. } 14 x^{2}+1=6 x^{2}+7 x \text { 10. } 4 x^{2}+4 x-8=1