Answer:
8a+2b+c
Step-by-step explanation:
13a-4b+8c
-(5a-6b+7c)
simplify second equation: -5a+6b-7c (multiplying -1 by each number)
now solve
13a-4b+8c
-5a+6b-7c
= 13a-5a-4b+6b+8c-7c (combining both equations, and like terms)
solve:
8a+2b+1c
= 8a+2b+c
Answer:
(1,9)
Step-by-step explanation:
For a function, each x value has only one y value. 2, 3, and 4 are already used up.
(1,9)
Answer:
3/2 of an hour to paint the entire room, so the answer is D).
Step-by-step explanation:
3/4*2=6/4=3/2
Move the decimal point to the right the number of places equal to the number of repeating digits. Subtract the original number. (Digits after the first instance of the pattern will be canceled.) Divide the result by a number of 9s equal to the number of repeating digits. Simplify the result.
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Example: 5.3181818_18
There are 2 repeating digits, so we subtract ...
... 531.8_18 -5.3_18 = 526.5
and divide by 99 . . . . . . two 9s, one for each of the two repeating digits
... = 526.5/99 = 5625/990 = 117/22 = 5 17/22
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More formally, if S is the value of the original number, and it has n repeating digits, you compute
.. (S·10^n - S)/(10^n -1) = S(10^n -1)/(10^n -1) = S
Answer:
Cost of a kit is $20
cost of a microscope is $80
Step-by-step explanation:
Here, we want to write a set of equations and solve
Let the cost of a microscope be $m while the cost of a kit be $k
Total cost of 38 microscopes will be 38 * m = $38m
Total cost of 47 kits = 47 * k = $47k
The sum of these is $3980
That will be;
47k + 38m = 3980 ••••••(i)
A microscope cost 4 times a kit
Mathematically;
m = 4k •••••••••(ii)
Substitute ii into i
47k + 38(4k) = 3980
47k + 152k = 3980
199k = 3980
k = 3980/199
k = $20
Recall;
m = 4k
m = 4 * 20 = $80