Solve Using the Quadratic Formula 3x^2+5x=2
Problem
3 x squared plus 5 x equals 2
Solution
Rearrange the equation into standard form a x squared plus b x plus c equals 0 by subtracting 2 from both sides.
3 x squared plus 5 x minus 2 equals 0
Identify the coefficients a b and c for the quadratic formula.
a equals 3
b equals 5
c equals negative 2
Apply the quadratic formula x equals the fraction with numerator negative b plus or minus the square root of b squared minus 4 a c and denominator 2 a by substituting the identified values.
x equals the fraction with numerator negative 5 plus or minus the square root of 5 squared minus 4 times 3 times negative 2 and denominator 2 times 3
Simplify the expression inside the square root (the discriminant).
x equals the fraction with numerator negative 5 plus or minus the square root of 25 plus 24 and denominator 6
x equals the fraction with numerator negative 5 plus or minus the square root of 49 and denominator 6
Evaluate the square root and solve for both possible values of x
x equals the fraction with numerator negative 5 plus or minus 7 and denominator 6
Calculate the first solution using the plus sign.
x equals the fraction with numerator negative 5 plus 7 and denominator 6 equals two sixths equals one third
Calculate the second solution using the minus sign.
x equals the fraction with numerator negative 5 minus 7 and denominator 6 equals negative 12 over 6 equals negative 2
Final Answer
x equals one third comma negative 2
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