For x^2-49
this is a diffarence of two perfect squares. I suggest that this is memorised.
a^2-b^2=(a-b)(a+b)
so x^2-7^2=(x-7)(x+7)
so to solve x^2+x-56 you want to find out what two numbers add to 1 and multiply to make -56
since -56 is negative we know that the two number are difarent signs so that eliminatess answers B and D.
if we try answer C -8+7=-1 so the answer is not C because we want +1 not -1
then we see that 8+(-7)=1 so the answer is A
The formula is
A=p e^rt
A future value?
P present value 2500
E constant
R interest rate 0.05
T time 10 years
A=2,500×e^(0.05×10)
A=4,121.80
Answer:
31.4 inches
You got to look at the line in between 31 and 32 so that means that it is the centimeter line so if it doesn't reach you basically just make it to a decimal.
please get more evidence
tell me if I am wrong or right
Answer:
The gas bill increases by $50
Step-by-step explanation:
We know that the increase in gas bills is directly proportional to the temperature setting. Let's take the increase in gas bills as g and increase in temperature setting as t. Thus, this can be written as:
g ∝ t
In every proportionality, there is a constant k, so it will be:
g = kt
It is mentioned that when the temperature setting increases by 4, the gas bill increases by $20, so in terms of the constant, we can write it as:
20 = k 4
We don't know the value of the constant, so we have to first find it out.
k = 20 ÷ 4
k = 5
Thus,
g = 5t
Now that we know the value of the constant, we can find by how much the gas bill will increase if the temperature setting increases by 10.
g = 5 × 10
g = <u>50</u>
∴ the gas bill increases by $50 when the temperature setting increases by 10 degrees Fahrenheit.
Answer: 
Step-by-step explanation:
As per given , we have
n=11
df = 11-1=10
Since population standard deviation is unknown , so we use t-test.
Critical t-value : 
Confidence interval for population mean :_
Hence, the 95% confidence interval for his mpg =
