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Solve using the quadratic formula.\newline8r2+5r7=08r^2 + 5r - 7 = 0\newlineWrite your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.\newliner=r = _____ or r=r = _____

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Q. Solve using the quadratic formula.\newline8r2+5r7=08r^2 + 5r - 7 = 0\newlineWrite your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.\newliner=r = _____ or r=r = _____
  1. Identify Coefficients: To solve the quadratic equation 8r2+5r7=08r^2 + 5r - 7 = 0 using the quadratic formula, we first identify the coefficients aa, bb, and cc from the standard form of a quadratic equation ax2+bx+c=0ax^2 + bx + c = 0. Here, a=8a = 8, b=5b = 5, and c=7c = -7.
  2. Apply Quadratic Formula: The quadratic formula is given by r=b±b24ac2ar = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}. We will substitute the values of aa, bb, and cc into this formula to find the solutions for rr.
  3. Calculate Discriminant: First, calculate the discriminant, which is the part under the square root in the quadratic formula: b24acb^2 - 4ac. This is 524(8)(7)=25+224=2495^2 - 4(8)(-7) = 25 + 224 = 249.
  4. Plug Values into Formula: Now, we can plug the values into the quadratic formula: r=5±24916r = \frac{-5 \pm \sqrt{249}}{16}. Since 249249 is not a perfect square, we will leave the square root as is for now.
  5. Find Solutions: We have two possible solutions for rr, corresponding to the '±\pm' in the formula. The first solution is r=5+24916r = \frac{-5 + \sqrt{249}}{16}, and the second solution is r=524916r = \frac{-5 - \sqrt{249}}{16}.
  6. Simplify Solutions: To simplify the solutions, we can leave them in the form of fractions or approximate them as decimals. The square root of 249249 cannot be simplified further, so we will leave it as 249\sqrt{249}. The fraction cannot be simplified further either, so the solutions in fraction form are r=5+24916r = \frac{-5 + \sqrt{249}}{16} and r=524916r = \frac{-5 - \sqrt{249}}{16}.
  7. Approximate Decimal Solutions: If we want to express the solutions as decimals, we can use a calculator to approximate 249\sqrt{249} and then divide by 1616. The approximate values are r(5+15.78)/160.67r \approx (-5 + 15.78) / 16 \approx 0.67 and r(515.78)/161.30r \approx (-5 - 15.78) / 16 \approx -1.30, rounded to the nearest hundredth.

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