Its 10
10 x 3 = 30
30/2 = 15
There are many ways to solve simultaneous linear equations. One of my favorite for finding integer solutions is graphing. The attached graph shows the solution to be ...
... (x, y) = (4, 7)
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You can also use Cramer's Rule, or the Vedic math variation of it, which tells you the solution to

is given by

Here, that means
... x = (9·67-5·75)/(9·8-5·3) = 228/57 = 4
... y = (75·8-67·3)/57 = 399/57 = 7
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A (graphing) calculator greatly facilitates either of these approaches.
Answer: 1 unit to the left, and 3 units down
Step-by-step explanation:
The mean is 20 and median is 20 the mode is 15 the range is 36 so that is your answer and hope this helps