Answer:
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Step-by-step explanation:
- Pythagorean theorem
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The expression (−81)(−9) will give the value of 729.
<u>Step-by-step explanation:</u>
The given expression is (−81)(−9)
.
The both numbers in the expression are negative numbers and they are given inside the brackets.
This means that, the negative numbers must be multiplied to get a final value.
<u>The rules in multiplication are :</u>
- Positive number × Positive number = positive number
- Negative number × Positive number = negative number
- Positive number × Negative number = negative number
- Negative number × Negative number = positive number
From the rules, it can be determined that the result of any two negative numbers will be a positive number.
So, eliminate option A) and B) because they have negative sign.
The expression (−81)(−9) = -81 × -9
⇒ 729.
Therefore, the option C) and D) are not in match with 729. None of the options are not the value of the given expression (−81)(−9).
Answer:
Original number 26.
Step-by-step explanation:
xy - two-digit number
1) x + y = 8
2) Original two-digit number can be written as
10*x + y
3) If the digits interchanged yx,
then the new number can be written as
10*y + x
4) Double the original number is
2*(10*x + y)
5) New number is 10 more than double the original number
(10*y + x) - (2*(10*x + y)) = 10
6) Now we have the system of 2 equations:
x + y = 8
(10*y + x) - (2*(10*x + y)) = 10 -----> 10y + x - (20x + 2y) = 10 ---> 8y - 19x = 10
x = 8 - y
8y - 19(8 - y) = 10
8y - 152 +19y = 10
27y = 162
y = 6
x = 8 - y = 8 - 6 = 2
x = 2
So, x =2, y = 6.
Original number 26.
Check:
Original number 26.
New number 62.
Double of the original number = 2*26= 52.
New number is 10 more than double the original number :
62 - 52 = 10 True
Answer:
2)8%
3)=
$
26.46
4)multiply $1.50 and 60%, which will give you 0.9. now multiply $1.50 and 0.9 and that'll give you$1.35. lastly, add $1.50 and $1.35 and that'll give you the answer which is $2.85.
5)15 % of $1580 is $237
6)25%
Step-by-step explanation:
Please mark brainliest
bc i answered all of them
-yasmine
If it’s just (-4) with nothing in front the answer is -4