Please see pic, I'd solved in it.
Answer:
D
Step-by-step explanation:
2y=10x
Divide both sides by 2.
y=5x
Now substitute this into the second equation.
The first-serve percentage of a
tennis player in a match is normally distributed with a standard deviation of
4.3%. If a sample of 15 random matches of
the player is taken, the mean
first-serve percentage is found to be 26.4%. The margin of error of the sample
mean is 83.71%.
Since both equations are equal to y, we can just combine them like this:
1/3x-3=-x+5
1/3x=-x+8
4/3x=8 (since x is 1x which is 3/3x)
x=6
Plug x back in:
y=-6+5
y=-1
So x=6 and y=-1
Hope this helped!