Solve the quadratic equation 3x^2 + x – 5 = 0 give answers to 3 decimal places

To solve this quadratic equation we should first see if it is possible to factorise it into two seperate brakets. In this case there are no numbers which multiply to give -5 and add to give 3. Thus we should resort to using the quadratic formula which is used when equations cannot be solved by inspection. The quadratic formula is x=(-b+-(b2-4ac)1/2)/2a. Values for a,b and c can be lifted from the question. ax2+b-c=0 so in this question a=3 b=1 and c=-5. Inputing these into the equation will give two results. The answers are x=1.135 or x=-1.468 both of these answers make the original equation true.

DR

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