Solve 5x^2 = 10x + 4 , to 2 decimal places.
First rearrange to get 5x2 - 10x - 4 = 0 , by subtracting 10x and 4 from both sides of the equation. Here, we can use the quadratic formula which is x = -b+- sqrt(b2 -4ac) / 2a. In our question a=5 , b=-10 , c=-4. Substituting these into the formula x = - (-10) +- sqrt(-102 -45-4)/2(5) =10+-sqrt(100+80) / 10 =10+- sqrt(180) / 10 So, x= 2.34, -0.34
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