Q. A function p is defined as p(x)=(x−a)(x−15)(x−20) where a is a constant. Given that p(7)=15, what is the value of a ?
Substitute and Set Equal: To find the value of a, we need to substitute x=7 into the function p(x) and set it equal to 15, as given by the condition p(7)=15.Calculation: p(7)=(7−a)(7−15)(7−20)=15
Simplify Expression: Simplify the expression by calculating the known values.Calculation: (7−a)(−8)(−13)=15
Multiply Constants: Multiply the constants (−8) and (−13) to simplify the equation further.Calculation: (7−a)(104)=15
Divide to Isolate: Divide both sides of the equation by 104 to isolate (7−a).Calculation: 7−a=10415
Simplify Right Side: Simplify the right side of the equation.Calculation: 7−a=10415≈0.144230769
Subtract and Solve: Subtract 7 from both sides to solve for a.Calculation: −a=0.144230769−7
Solve for a: Solve for a by multiplying both sides by −1.Calculation: a=7−0.144230769
Complete Calculation: Complete the calculation to find the value of a.Calculation: a≈7−0.144230769≈6.855769231
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