Answer:
1
Step-by-step explanation:
x-y+xy=1-1+1*1=0+1=1
Step 1) turn 1.9 into an improper fraction.
= 19/10
step 2) find a least common denominator between 10 and 12.
= 60
(10x6 and 12x5)
step 3) convert the fractions so they have the same denominator.
= 19x6 is 114.
10x6= 60.
= 11x5 is 55.
12x5 is 60.
now you have your new fractions.
step 4) subtract.
= 114/60 - 55/60 is 59/60.
step 5) simplify.
the answer is either 0.9833... (3 repeating) or just 59/60 (you can't simplify the fraction any further).
Answer:

Step-by-step explanation:
So we have:

And we want to solve for π.
First, divide both sides by h:

Now, divide both sides again by r²:

And this is our answer :)
Adding and subtracting with negative numbers
First, recognize that adding and subtracting are, from one viewpoint, the same thing. Subtracting a number is the same thing as adding the negative of that number. For example, 4 – 12 is the same as 4 + –12 (which, because the order of terms doesn't matter with addition, is the same as –12 + 4). With that in mind, here are the rules for adding with negative and positive numbers:
If both numbers are positive, then the answer is positive.
If both numbers are negative, then the answer is negative.
If the numbers have different signs, the answer takes the sign of the higher number.
Subtracting a negative number is the same as adding the positive of that number. For example, 5 – –4 is the same as 5 + 4.
Multiplying and dividing with negative numbers if the numbers have different signs, the answer is negative.