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
Yuto is correct because he isolated the variable correctly and reversed the inequality symbol.
x < 3
Answer:
-3x(7x+8)
Step-by-step explanation:
-3x^2-18x^2-24x
-3x(x+6x+8)
-3x(7x+8)
Yes, 104.12 is greater than 104.02.
1)
you have similar triangles(ABC, ADE), so their side length ratios are equal
8/2=4/CE
CE*4=4
CE=1
2)
angle bisector theorem:
CD/DA=BC/BA
CD/DA=10/8
I:AD=10CD/8
we also know AC=AD+CD=6
II:CD=6-AD
insert II in I:
AD=10(6-AD)/8
=5(6-AD)/4
=(30-5AD)/4
4AD=30-5AD
9AD=30
3AD=10
AD=10/3