8. A
9. C
10. D
Those are the answers
Answer:
Step-by-step explanation:
x^2+20=2x move 2x to the left
x^2-2x+20=0
Quadratic formula =
x=1± i√19
Yes....because a terminating decimal can be turned into a fraction, making it rational
Answer: 26 years old
Step-by-step explanation:
- Create an equation with Austin as x and Jamie as x+69 (I just like workin with addition signs more)= 4(x-3)= x+69-3
- Simplify the equations --> 4x-12=x+66
- Solve the equation: 3x-12=66 --> 3x=78 --> x=26
This is the same as other age problems, just with the extra step of distributing the multiplication.
A=Pe^(rt)
P = 800g
t = 8 years
A = 450g
r = This is what we will try and find to start with
450=800e^(r*8)
After running the math through a calculator, we end with r = -0.07192
Now we just re-input this information into our equation: A=800e^(-0.07192*16)
A=800e^(1.15072)
Now we will re-write the equation using the negative exponent rule:
A = 800 1/e^1.15072
Combine right side:
A = 800/e^1.15072
Then do the math:
A = 253.12709836......
That will give us A = 253 (rounded to the whole number)
I hope this helps! :)
