Given two terms a, b.
Sum of terms = a+b
Difference of terms = a-b
Product of sum and difference (do not forget parentheses)
=(a+b)(a-b)
which can be expanded as=a^2-b^2
We can make use of this property to calculate with lightning speed, assuming you know the squares of numbers.
For example,
8*6=(7+1)(7-1)=7^2-1^2=48
9*7=(8+1(8-1)=8^2-1^2=64-1=63
5*15 = (10+5)(10-5)=10^2-5^2=75
22*18=(20+2)(20-2)=20^2-2^2=400-4=396
63*57=(60+3)(60-3)=60^2-3^2=3600-9=3591
128*112=(120+8)(120-8)=120^2-8^2=14400-64=14336
We can go on and on!
Answer:
yes
Step-by-step explanation:
because we are simply "adding" 2 negative numbers.
-8n + -7 = -7 + -8n
as long as we flip the terms around with their signs, the commutative principle of addition applies.
what we CANNOT do is e.g.
8n - 7 = 7 - 8n
THERE would be a problem.
but again, by also keeping the signs with the terms, it is all OK.
so, yes, we could also do
8n - 7 = -7 + 8n
that is true again.
I have no clue. i’m only here bc i need to ask a question but ic gl
Answer:
a) reject H0
Step-by-step explanation:
The null and alternative hypotheses:
H0: the relative risk for moderate beer drinkers as compared to nondrinkers = 1
Ha: the relative risk for moderate beer drinkers as compared to nondrinkers ≠ 1
The level of significance, α = 0.1
Since the confidence interval for the relative risk of hypertension in moderate beer drinkers as compared to nondrinkers (0.47 to 0.90) does not contain the relative risk of 1, the null hypothesis will be rejected at the specified level of significance, 0.1. Therefore, the conclusion is to reject H0.