Option D. 2(n + 9) is the right answer
Step-by-step explanation:
The word problems are converted into mathematical problems to solve simply.
for the given problem
"two times the sum of a number and 9"
Let n be a number then
when there is and between two things they are performed first then next operation is performed so
the sum of a number and 9

Then
two times the sum of a number and 9

Hence,
Option D. 2(n + 9) is the right answer
Keywords: Mathematical notation
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Answer:
The answer to the first one is y
=
4/7
x
−
13
/7
The second one is already in standard form
Step-by-step explanation:
Answer:
Part 1) 10 modules per floor
Part 2) Two different rectangular prism
Step-by-step explanation:
Part 1)
Let
x ----> the number of modules
y ---> the number of stories
we have

Divide the number of modules by the number of stories
so

Part 2) How many different rectangular prisms could be made from that number?
The number is 10
Look at the factors of 10
They are 1,2
,4,5 and 10
Pick any two of these factors and determine if there is a third value from this list so that the product of the three factors is 10
There are 2 combinations that will work :
1
0×1×1
2
×5×1
What kind of question is this lol ? i don’t even understand it
Answer:
D
Step-by-step explanation:
The basic equation to solve this would be D = RT, which is
D is Distance
R is Rate (speed)
T is time
To find total distance D, we can find individual distances for two legs of the whole.
First Leg:
R = 8
T = a
D = 8a
Second Leg:
R = 7.5
T = b
D = 7.5b
Total distance D is:
D = 8a + 7.5b
Moreover, we know student runs 45 minutes in total hence a + b = 45 or we can say a = 45 - b, so we can replace this in the equation found:
D = 8a + 7.5b
D = 8(45 - b) + 7.5b
Answer choice D is right.