Find all values of c such that

Step-by-step explanation:
c/(c - 5) = 4/(c - 4)
By Cross-multiplying,
We have c(c - 4) = 4(c - 5).
=> c² - 4c = 4c - 20
=> c² - 8c + 20 = 0
Since the discriminant is negative,
there are no real solutions for c.
However, there exist complex solutions for c.
Using the Quadratic Formula,
c = [8 ± √(-16)]/2
=> c = 4 ± √(-4)
=> c = 4 ± 4i or c = 4(1 ± i).
Answer:
No real solutions.
Step-by-step explanation:
Step 1: Cross-multiply.
c/c−5=4/c−4
c*(c−4)=4*(c−5)
c^2−4c=4c−20
Step 2: Subtract 4c-20 from both sides.
c^2−4c−(4c−20)=4c−20−(4c−20)
c^2−8c+20=0
For this equation: a=1, b=-8, c=20
1c^2+−8c+20=0
Step 3: Use quadratic formula with a=1, b=-8, c=20.
c= −b±√b^2−4ac/2a
c= −(−8)±√(−8)2−4(1)(20)/2(1)
c= 8±√−16/2