Problem: If 32x+9=10(3x), then the value of (x2+1) is
Answer Choices:
A. 1 only
B. 5 only
C. 1 or 5
D. 2
E. 10
Solution:
Let y=3x and the given equation is equivalent to y2−10y+9=0 or (y−9)(y−1)=0. Hence y=3x=9 or 1,x=2 or 0 so that x2+1=5 or 1 .