Question

What are the solutions of the quadratic equation (x – 8)2 – 13(x – 8) + 30 = 0? Use u substitution to solve.

Answer 1

It is a quadratic
where x-8 is the squared term
do
x-8=u

u^2-13u+30=0

solve
u=$\frac{-b+/- \sqrt{b^2-4ac} }{2a}$
u=$\frac{-(-13)+/- \sqrt{(-13)^2-4(1)(30)} }{2(1)}$
u=$\frac{13+/- \sqrt{169-120} }{2}$
u=$\frac{13+/- \sqrt{49} }{2}$
u=$\frac{13+/- 7 }{2}$
u=$\frac{20} }{2}$ or u=$\frac{6 }{2}$
u=10 or 3

10=x-8 or 3=x-8
18=x or 11=x

x=11 and/or 18

Answer 2

Answer:

It is 11 and 18 positive not negative numbers

Step-by-step explanation: