7 Units.
8(1)+9= 17
8(2)+9=25
8(3)+9=33
33-25=7. 25-17=7
Answer:
20-15z
Step-by-step explanation:
-1+21-15z
20-15z
-7 = x/2 + 1
Subtract one from both sides
-8 = x/2
Multiply two on both sides
-16 = x
Answer, x = -16
Checking,
-7 = (-16/2) + 1
-7 = -8 + 1
-7 = -7
Answer: 6 m
This statement:
"Jared has run two-thirds of an 18-kilometer race" can be written as an equation:

This means two-thirds of 18 km is equivalent to 12 km
If we substract this value to the total, we have the values of the kilometers left to run:

Therefore the correct option is D
After 2.0 years, the 4.0 mg sample decays to 2.0 mg.
After another 2.0 years (total 4.0 years), the 2.0 mg sample decays to 1.0 mg.
And after another 2.0 years (total 6.0 years), the 1.0 mg sample decays to 0.50 mg.
So it takes 6.0 years for 4.0 mg to decay to 0.50 mg.