Ur gonna have to pick an equation and solve for a variable.
2x - 2y = 6
2x = 2y + 6 ...divide everything by 2 because u want x by itself
x = y + 3
now we sub y + 3 in for x in the other equation
14x - 2y = 78
14(y + 3) - 2y = 78...distribute thru the parenthesis
14y + 42 - 2y = 78...subtract 42 from both sides, cancelling the 42 on the left
-42 -42
-----------------------
14y - 2y = 36 ...simplify
12y = 36...divide by 12 on both sides, cancelling out the 12 on the left
y = 36/12
y = 3
now , we already know that x = y + 3...and we know y = 3...so sub in 3 for y and solve for x
x = y + 3
x = 3 + 3
x = 6
solution is (6,3)
it is always a good idea to check ur answer by subbing it into one or both of the equations to see if it is correct
2x - 2y = 6......(6,3)...x = 6 and y = 3
2(6) - 2(3) = 6
12 - 6 = 6
6 = 6 (correct)
so yes, ur solution is (6,3)
Answer:
1. He ignored 4 on the first line
2. 9 - 2x
Step-by-step explanation:
4 - 2(x + 5)
4 - 2x + 5
9 - 2x
You replace the y with f(x)
So it becomes f(x)=2x+1
Answer:
multiply by 25 also.
Step-by-step explanation:
If the scores are multiplied by 25, that means that the mean will also multiply by 25. Since the mean and the scores all increased by 25 times, the standard deviation will increase by 25 times.
If instead, you added 25 (or any other number) to each score, then the standard deviation would not change. The mean and each score will increase by 25, bu the difference between them will not change.