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Question
Find the roots of the quadratic equation by using the quadratic formula in the following:
5x2 + 13x + 8 = 0
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Solution
The quadratic formula for finding the roots of quadratic equation
ax2 + bx + c = 0, a ≠ 0 is given by,
x = `(-b +- sqrt(b^2 - 4ac))/(2a)`
∴ x = `(-13 +- sqrt((-13)^2 - 4(5)(8)))/(2(5))`
= `(-13 +- sqrt(9))/10`
= `(-13 +- 3)/10`
= `-1, - 8/5`
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