15
A total of 39 took psychology. 12 of those took that and science and another 10 of those took that and history. 2 people took all three. 12+10+2 = 24 students who took psychology along with another class. To find the number of students who took ONLY psychology, you would take 39 and subtract 24, which leaves you with 15.
Answer:
1.The chosen topic is not meant for use with this type of problem. Try the examples below.
(
6
,
−
3
)
(
6
,
4
)
(
9
,
7
)
Your answer is 9s^2-9st+6st-6t^2
Step-by-step explanation:
b^2-4b+3=0
b²-3x-b+3=0
b(b-3)-1(b-3)=0
(b-3)(b-1)=0
either
b=3 or b=1
.
2n^2 + 7 = -4n + 5
2n²+4n+7-5=0
2n²+4n+2=0
2(n²+2n+1)=0
(n+1)²=0/2
:.n=-1
.
x - 3x^2 = 5+ 2x - x^2
0=5+ 2x - x^2-x +3x^2
0=5+x+2x²
2x²+x+5=0
comparing above equation with ax²+bx +c we get
a=2
b=1
c=5
x={-b±√(b²-4ac)}/2a ={-1±√(1²-4×2×5)}/2×1
={-1±√-39}/2
Answer:

40 comic books
Step-by-step explanation:
Let x be the Jill comic books.
Given:
Jill sold half of her comic books and then bought sixteen more. She now has 36.



Therefore the algebraic equation of the given statement.
--------(1)
Now we solve above equation for x.
Subtract by 16 both side of the equation 1.


Multiply by 2 both side of the above equation.


Therefore, Jill had 40 comic books.