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
Answer:
30a + 18b
Step-by-step explanation:
6(5a+3b)
Just multiply the six in both numbers
( 6x5a) + (6x3b)
= 30a +18b
Hope this helps =)
Answer:
day 0, day 120
Step-by-step explanation:
You want to find the value of x that makes both y-values be the same:
y = y
30x +10 = -x^2 +150x +10
x^2-120x = 0 . . . . subtract the right side of the equation
x(x -120) = 0 . . . . . factor
Values of x that make this true are x=0 and x=120.
The same number of each car was sold on day 0 and day 120.
He walked the same distance to school and back home.
I hope this helped! :-)
