Solve 5a^2-2a-4 - ScanMath

Evaluate

5 a^{2} - 2 a - 4

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

5 a^{2} - 2 a - 4 = 0

Substitute a= 5,b= - 2 and c= - 4 into the quadratic formula a = \frac{- b \pm b ^{2} - 4 a c}{2 a}

a = \frac{2 \pm ( - 2 ) ^{2} - 4 \times 5 ( - 4 )}{2 \times 5}

Simplify the expression

a = \frac{2 \pm ( - 2 ) ^{2} - 4 \times 5 ( - 4 )}{10}

Simplify the expression

More Steps

a = \frac{2 \pm 84}{10}

Simplify the radical expression

More Steps

a = \frac{2 \pm 2 21}{10}

Separate the equation into 2 possible cases

a = \frac{2 + 2 21}{10} a = \frac{2 - 2 21}{10}

Simplify the expression

More Steps

a = \frac{1 + 21}{5} a = \frac{2 - 2 21}{10}

Simplify the expression

More Steps

a = \frac{1 + 21}{5} a = \frac{1 - 21}{5}

Solution

a_{1} = \frac{1 - 21}{5}, a_{2} = \frac{1 + 21}{5}

Alternative Form

a_{1} \approx - 0.716515, a_{2} \approx 1.116515

Find the roots