10+ ?= 49
⇒ ?= 49-10
⇒ ?= 39
10 plus 39 can give you 49~
Step-by-step explanation:
Sn=n/2(2a+(n-1)d)
910=n/2{2a+(n-1)d}
1820=n{2a+(n-1)d}
1820=20{2a+(20-1)d}
1820=20{2a+19d}
91=2a+19d
An=a+(n-1)d
95=a+(20-1)d
95=a+19d
91=2a+19d
---------------
4=-a
a=-4
91=2a+19d
91=2(-4)+19d
91=-8+19d
91+8=19d
99=19d
d=99/19
A=-4
Yes, I agree with the researcher's method. All the values of 
in the table correspond to the values of n by using their formula.
Step-by-step explanation:
Step 1:
If we substitute the values of n in the researcher's equation and we get the right values of , we can agree with the researcher's method.
The researcher's formula is 
Here is the wombat population and n is the number of years.
Step 2:
When n = 1, 
when n = 2, 
when n = 3, 
when n = 4, 
when n = 5, 
As all the values correspond to the values on the table, I agree with the researcher's method.
Answer:
C. 2x^2-7x+7
Step-by-step explanation:
(3x^2-2x+2)-(x^2+5x-5) <em>Given</em>
From the given you will subtract like terms from both parenthesis.
3x^2-x^2=2x^2
-2x-5x=-7x
2-(-5)=7
