Answer:
(2,4)
Step-by-step explanation:
We have the system:
y=x+2
y=3x-2.
This is already setup for substitution.
I'm going to replace my first y with what the second y equals.
That is, I'm going to write 3x-2=x+2.
Time to solve the following for x:
3x-2=x+2
Subtract x on both sides:
2x-2= 2
Add 2 on both sides:
2x. = 4
Divide both sides by 2:
x. = 2
Now that we know x=2 and we have an equation that relates x to y: either y=x+2 or y=3x-2, doesn't matter which we use, we can find y.
So we y=x+2 with x=2 which means y=2+2=4.
So the solution, the intersection, is (2,4).
Answer: she scored 69 points on the second test.
Step-by-step explanation:
Let x represent the number of points that she scored in the first test.
Let y represent the number of points that she scored in the second test.
If her mean score was 75, it means that
(x + y)/2 = 75
x + y = 75 × 2
x + y = 150- - - - - - - - - 1
If she scored 12 points more on the first test than the second test, it means that
x = y + 12
Substituting x = y + 12 into equation 1, it becomes
y + 12 + y = 150
2y + 12 = 150
2y = 150 - 12
2y = 138
y = 138/2
y = 69
:
No.
Half of 48 would be 24, not 21
<3
Answer: C & D
Step-by-step explanation:
I believe the answer would be 3/40
