Answer:
(8,-5)
Step-by-step explanation:
Add the equations in order to solve for the first variable. Plug this value into the other equations in order to solve for the remaining variables.
Point Form:
(
8
,
−
5
)
Equation Form:
x = 8
, y = −
5
Answer:
If you're looking for a shortcut, I usually find the number 1 less than what you are multiplying 9 by, this case 8, and then add a number that gets to 9.
So 9x6 would be:
5+4=9
54
Step-by-step explanation:
When multiplying by 9s the product's two numbers added together =9.
Sorry if this is confusing. Hope this helps though.
Answer: 30g
Step-by-step explanation:
In this question (t½) of isotope is 40 days, which means that after 40 days half of the sample would have decayed and half would be left as it is.
After 40 days ( first half life) 240 /2 = 120 g decays and 120 g remains left.
After another 40 days ( two half lives or 80 days) 120 /2 = 60 g decays and 60 g remains left .
after three half lives or 120 days, 60/2 = 30g decay and 30 g of the isotope will be left.
