x2+kx−14=0In the given equation, k is a constant. The equation has solutions at 7 and −2 . What is the value of k ?Choose 1 answer:(A) −9(B) −5(C) 5(D) 9
Q. x2+kx−14=0In the given equation, k is a constant. The equation has solutions at 7 and −2 . What is the value of k ?Choose 1 answer:(A) −9(B) −5(C) 5(D) 9
Use Given Solutions: Since the solutions to the quadratic equation are given as 7 and −2, we can use the fact that if x=a and x=b are solutions to the equation x2+kx−14=0, then the equation can be factored as (x−a)(x−b)=0.
Factor the Equation: Let's factor the equation using the given solutions: (x−7)(x+2)=0.
Expand Factored Form: Now, we expand the factored form to find the quadratic equation: x2−7x+2x−14=x2−5x−14=0.
Compare Coefficients: Comparing the expanded form x2−5x−14=0 with the given equation x2+kx−14=0, we can see that the coefficient of x must be equal to k. Therefore, k=−5.
More problems from Transformations of absolute value functions: translations and reflections