Question

Find the roots of 4x2+3x+5=0 by the method of completing square

plz smone explain this answer..

Answer 1

$4x {}^{2} + 3x + 5 = 0 \\ 4x {}^{2} + 3x = - 5 \\ b = 3 \: \: b \frac{1}{2} = 3 \div 2 \\ (b \div 2) { }^{2} = (3 \div 2) ^{2} = 9 \div 4 \\ adding \: 9 \div 4 \: on \: both \: sides \\ 4x {}^{2} + 3x + 9 \div 4 = - 5 + 9 \div 4$