Answer:
D year 15
Step-by-step explanation:
Given:
y= 8x^2-40x+6
year is the best prediction for when 1206
Finding value of x for y=1206
8x^2-40x+6= 1206
8x^2-40x+6-1206=0
8x^2-40x-1200=0
Solving the above by quadratic formula:
x= 
= 
x= 15 and x= -10
As year can not be negative, hence correct answer is
D: year 15!
Answer:
50
Step-by-step explanation:
20% is the same as 0.2 times something.
So you can create the equation 0.2x = 10. The solution of this equation is x=50.
Answer:

Step-by-step explanation:
We are given the expression 
This means that we are looking for two numbers that would add together to give us 12 and multiply to give us 27.
The two numbers that fit this description are 3 and 9.
This means that the factored form of the expression would be

Answer:
Divide by 1000.
Step-by-step explanation:
For example, 1 joule is 0.001 kilo joule.
1 divided by 1000 is 0.001.
If there were 30 joules, there would be 0.032 kilo joules.
Step-by-step explanation:
1. vertically opposite angles are the same
b = 42
360 - (42 + 42)
360 - 84 = 276
276 ÷ 2 = 138
c = 138
2. angles in a triangle sum to 180
right angles = 90
180 - (90 + 62)
180 - 152 = 28
angle S = 28
3. 1st question no, unless one angle is given a number. angles are the same vertically opposite so the other 2 angles are also vertically opposite but angle is different size but by adding the 2 different angles, make them supplementary as they sum to 180. 2nd question yes. you could have 4 right angles.