Answer:The diagram shows a square ABCD.
D
N
bu
A
M
I
Mis the midpoint of AB.
Nis the midpoint of AD.
The area of the shaded triangle AMN is 18 cm
Work out the area of triangle MCN.
5b is the area of MCN
Step-by-step explanation:
Answer:
and 
The ordered pair solutions are
,
,
, and
.
Step-by-step explanation:
I'm assuming the system is
:


























Therefore,
and 
The ordered pair solutions are
,
,
, and
.
Answer:
A book is worth $1 and a DVD is worth $12.
Step-by-step explanation:
The equations (2 unknowns and two equations, d is for a DVD and b is for a book):
For David: 3d+4b=40
For Anna: d+6b=18
Now multiply the second equation with -3 and add to the first equation:
3d+4b=40
−3d−18b=−54
Combined equation: −14b=−14 and b=1 (means that each book is worth $1).
Now for DVD price, use the second equation:
d=18−6 or d=12 (means that each DVD is worth $12).
A book is worth $1 and a DVD is worth $12.