Answer:
b = 
Step-by-step explanation:
Yea something is not right.if y=6 then you cant solve the system because you end up with x^2-4x-1
1/2 chance per flip
1/2 times 4 is 1/8
its 1/8 chance or 12.5%
Answer:
y=3x.........1
y=x^2-10.......2
substituting value of eq 1 to 2
3x=x^2-10
x^2-10-3x=0
x^2-3x-10=0
x^2-5x+2x-10=0
X(x-5)+2(x-5)=0
(x-5)(X+2)=0
then
X=5 or X=-2
again
y=??
when X=5
y=3×5=15
when X=-2
y=-6