Answer:
the mean is 4
Step-by-step explanation:
add 6+5+6+1+5+5+0=28
then divide 28 by how many numbers there are so it would be 7 numbers
28 divided by 7 equals 4
Answer:
x=2i, -2i
Step-by-step explanation:
Answer:
any coordinate outside the parabola is a reasonable answer.
Step-by-step explanation:
test the solution (0, 0) and if if that number is greater than 0 then the rest of the points outside on the inside are.
x = 0
y = 0
(0)^2 - 2(0) - 3 = -3
-3 is less than 0 so (0, 0) is not a possibility so any coordinate outside the parabola is a reasonable answer.
Answer:
AC=9 cm
ABC is not a right angled triangle
Step-by-step explanation:
AB=8cm
BC=5cm
22=AB+BC+AC
AC=22-8-5
AC=9
since AC is the longest,
using Pythagoras theorem
AC^2=BC^2+AB^2
9^2=8^2+5^2
81=64+25
81=89
therefore, it is not a right angled triangle
Answer:
750 grams of 60% alloy
Step-by-step explanation:
Define x = amount of 60% alloy and y = amount of 20% alloy
Equating the amounts of gold:
0.6x+0.2y = 1000(0.5)
Since there must be 1000 grams total:
x+y = 1000
Writing the 2 resulting equations together:
0.6x + 0.2y = 500
x + y = 1000
Multiply the first equation by 5:
3x + y = 2500
x + y = 1000
Subtracting the 2nd equation from the 1st:
2x = 1500
x = 750
Answer: 750 grams of 60% alloy