Answer:
87
Step-by-step explanation:
Answer:
This is a reflection about the x-axis.
Step-by-step explanation:
A reflection about the x-axis has the rule
[x,y]-> [x,-y].
Therefore
M[x,y] = [x,-y}
Let M=
|a b|
|c d|
Then the matrix multiplication gives
ax+by=x.............(1)
cx+dy=-y............(2)
Solving the previous equations (1) and (2) gives
a=1, b=0
c=0, d=-1
giving M as
|1 0|
|0 -1|
X is the number of hours studied, so replace x with 3 in the equation:
y = 6.8(3) + 60
y = 20.4 + 60
y = 80.4
Round down to 80.
The answer would be A.
8
5
8
5
hopefully its right i'm not good at this kind of stiff
