Answer:
Step-by-step explanation:
Whenever we are doing unit conversions, we have to remember to make the first ratio and then each successive ratio should be put <em>in such a way</em> that the top and bottom cancels out with each unit and whatever we want, remains.
A simple example would be if we were to just convert from cm to mm. Suppose we want to convert 5 centimeters to millimeters. We can write the ratios is 2 ways:
First:
Second:
The first one is correct since we want mm, mm should be on top and cm should be on bottom form cm and cm to get canceled.
Now, for our problem, we want mm on top and day on bottom. So, cm and year should cancel. Looking at the first choice, the conversion factors are correct & skimming through, we see that
cm and cm cancels (top and bottom), also year and year cancels (top and bottom), it will leave us with mm on top and days on bottom, <em>which is what we want</em>.
First answer choice is right.
Answer:
Step-by-step explanation:
4x − y = −11
2x + 3y = 5
lets multiply the second equation by -2 and add it to the first:
4x − y = −11
-4x - 6y = -10
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0 - 7y = -21
y = -21/-7
y = 3
now we substitute this result in the first equation to find x:
4x − y = −11
4x - 3 = -11
4x = -8
x = -8/4
x = 2
so the solution is y = 3 and x =2
4x − 9y = −21
−10y = −30
we solve for y
−10y = −30
y = -30/-10
y = 3
and substitute in the first equation:
4x − 9y = −21
4x − 9(3) = −21
4x - 27 = -21
4x = 6
x = 6/4 = 3/2
so the solution is x = 3/2 and y = 3
4x + 3y = 5
2y = −6
we solve for y:
2y = −6
y = -6/2
y = -3
we do substitute in the first equation:
4x + 3y = 5
4x + 3(-3) = 5
4x - 9 = 5
4x = 14
x = 14/4
x = 7/2
so the solution is x = 7/2 and y = -3
7x − 3y = −11
9x = −6
we solve for x:
9x = −6
x = -6/9
x = -2/3
then we substitute in the first equation the result found:
7x − 3y = −11
7(-2/3) − 3y = −11
-14/3 - 3y = -11
we multiply by 3 to eliminate fractions:
-14 - 9y = -33
9y = 19
y = 19/9
so the solution is x = -2/3 and y = 19/9
12x − 3y = −33
14x = −28
we solve for x:
14x = −28
x = -28/14
x = -2
then we substitute in the first equation:
12x − 3y = −33
12(-2) − 3y = −33
-24 - 3y = -33
3y = 9
y = 3
then the solution is x = -2 and y = 3
Step-by-step explanation:
This is the correct answer.
Even according to calculator and working.
So not quite sure why those options are incorrect?
Ok so to solve to first one u do this:
62.4 - 31.53, which gives u 30.87. and then u add 30.87 and 31.33, and u get 62.4
for the second one u do the same thing.
FC is median..
Median is a line from a vertex that equally divides the opposite side...
here FC divides DB therefore it is a median.....
HOPE IT HELPS YOU '_'
