Baiiiii :D
Wow, this is so awesome!!!!
I don't know these people (except CPhill and Melody), but they sound awesome!
I feel you too.
For #5, I find that annoying, too.
1. I'm not sure, I'm not a mod here.
2. They are locked, I think.
Can you write one question at a time, please?
Here is a formula... (a+b)(a-b)=a^2-b^2
So, let's use that formula here!
\((sqrt(23)+sqrt(5))(sqrt(23)-sqrt(5))\)
would equal (sqrt(23))^2 - (sqrt(5))^2
This is equal to 23-5, which is 18.
Calculators are helpful, but if you use them too often, you might not be able to do calculations as simple as 38*25! Also, when doing Algebra, calculators are allowed, but most teachers don't allow calculators in calculus. Calculators aren't allowed in competition, either. So, it is best to practice without a calculator!
1) A
2) B
3) A
The first one, the 20 affects the answer a lot!
Let's first find the slope!
(-3-6)/(5-3)=-9/2=-4.5
y=-4.5x+b
Let's find b now!
-3=-13.5+b
b=-10.5
So, our equation is y=-4.5x-10.5