Answer:
The area of the triangle is of 21 units of area.
Step-by-step explanation:
The area of a triangle with three vertices
is given by the determinant of the following matrix:

In this question:
Vertices (3,0) (9,0) (7,6). So




The area of the triangle is of 21 units of area.
Answer:
CBD is 120 degrees
Step-by-step explanation:
x=30
4x30+30+30=180
Answer:
She is wrong.
Step-by-step explanation:
The mean score is
7 + 8 + 3 + 0 + 2= 20
We then divide it by the number which is 5
20/5= 4.
Therefore, Maria is wrong.
This is because she divided by 4 instead of 5, as she didn't include the rational number 0.
Answer:
Step-by-step explanation:
MX = XN
5r² + 2r + 52 = 4r² + 12r + 27
5r² - 4r² + 2r - 12r + 52 - 27 = 0
r² - 10r + 25 = 0
(r - 5)² = 0
r - 5 = 0
r = 5
4r² + 12r + 27
4•5² + 12•5 + 27
4•25 + 60 + 27
100 + 60 + 27
187
The Second one
I hope I helped you.