Solve 2x^2-21x-4 - ScanMath

Evaluate

2 x^{2} - 21 x - 4

To find the roots of the expression,set the expression equal to 0

2 x^{2} - 21 x - 4 = 0

Substitute a= 2,b= - 21 and c= - 4 into the quadratic formula x = \frac{- b \pm b ^{2} - 4 a c}{2 a}

x = \frac{21 \pm ( - 21 ) ^{2} - 4 \times 2 ( - 4 )}{2 \times 2}

Simplify the expression

x = \frac{21 \pm ( - 21 ) ^{2} - 4 \times 2 ( - 4 )}{4}

Simplify the expression

More Steps

x = \frac{21 \pm 473}{4}

Separate the equation into 2 possible cases

x = \frac{21 + 473}{4} x = \frac{21 - 473}{4}

Solution

x_{1} = \frac{21 - 473}{4}, x_{2} = \frac{21 + 473}{4}

Alternative Form

x_{1} \approx - 0.187141, x_{2} \approx 10.687141

Find the roots