Answer:
\sqrt(217)
Step-by-step explanation:
(19)^2=(12)^2
361 - 144 + 217
\sqrt(217)
Ming-Li had $75 to begin with. Just add all the numbers
Consider the trinomial 
1. Find the discriminant:
2. Find the roots of given trinomial:
3. Conclusion: given trinomial has two different real roots.
Let number of yellow marbles = x
Let number of red marbles = y
Let number of blue marbles = z
Given that Finley has 152 yellow, red, and blue marbles in a bag.
So we get equation:
x+y+z=152...(i)
"He has seven more red marbles than yellow marbles" means:
y=x+7...(ii)
"three times as many blue marbles as yellow marbles." means:
z=3x...(iii)
Now we just need to solve those equations to find the answer.
Plug (ii) and (iii) into (i)
x+(x+7)+(3x)=152
x+x+7+3x=152
Which looks similar to choice (B)
5x+7=152
5x=145
x=29
Hence final answer is choice B.
Required equation is
x+x+7+3x=152
Number of yellow marbles = 29
