Solve using the quadratic formula.5j2−6j−7=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.j=_____ or j=_____
Q. Solve using the quadratic formula.5j2−6j−7=0Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.j=_____ or j=_____
Identify coefficients: Identify the coefficients a, b, and c in the quadratic equation5j2−6j−7=0. The quadratic equation is in the form aj2+bj+c=0, so by comparison, we have: a=5b=−6c=−7
Substitute values: Substitute the values of a, b, and c into the quadratic formula.The quadratic formula is j=2a−b±b2−4ac.Substitute a=5, b=−6, and c=−7 into the formula to get:j=2⋅5−(−6)±(−6)2−4⋅5⋅(−7)
Simplify discriminant: Simplify the expression under the square root (the discriminant).Calculate the discriminant: (−6)2−4⋅5⋅(−7)=36+140=176.
Continue simplifying: Continue simplifying the quadratic formula with the discriminant.Now we have:j=106±176
Simplify square root: Simplify the square root, if possible.The square root of 176 cannot be simplified to an integer, so we leave it as 176.
Calculate possible solutions: Calculate the two possible solutions for j.j=106+176 or j=106−176
Round values: Round the values of j to the nearest hundredth, if required.j≈(6+13.27)/10 or j≈(6−13.27)/10j≈19.27/10 or j≈−7.27/10j≈1.93 or j≈−0.73
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