Q. Solve the equation 2x2+15x+4=−1 to the nearest tenth.Answer: x=
Set Equation to Zero: First, we need to set the equation to zero by adding 1 to both sides of the equation.2x2+15x+4=−12x2+15x+4+1=−1+12x2+15x+5=0
Use Quadratic Formula: Next, we will use the quadratic formula to solve for x. The quadratic formula is x=2a−b±b2−4ac, where a, b, and c are the coefficients from the quadratic equationax2+bx+c=0. In our equation, a=2, b=15, and c=5.
Calculate Discriminant: Now, we calculate the discriminant, which is the part under the square root in the quadratic formula: b2−4ac. Discriminant = (15)2−4(2)(5) Discriminant = 225−40 Discriminant = 185
Apply Quadratic Formula: Since the discriminant is positive, we will have two real solutions. We will now apply the quadratic formula.x=2×2−15±185x=4−15±185
Calculate First Solution: We will calculate the two solutions separately.First solution:x=4−15+185x≈4−15+13.601x≈4−1.399x≈−0.34975Rounded to the nearest tenth, x≈−0.3
Calculate Second Solution: Second solution:x=4−15−185x≈4−15−13.601x≈4−28.601x≈−7.15025Rounded to the nearest tenth, x≈−7.2
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