Answer:
A= 75.06 Sq Cm
Step-by-step explanation:
Please refer to the picture attached with this.
In ΔABD
AB = 8.5 , AD = 6 and say BD = x
Applying Pythagoras theorem in this triangle
Pythagoras theorem says
where c is the side opposite to the right angle, and b and a are the other two sides of the right angled triangle.
Hence side 
a = 6.02+19
a = 25.02
Now we apply the formula for area of a triangle which is given as
Where b is the base , here we have base as a = 25.02
h is the height , here h = 6
Putting these values in Formula we get
Hence Area of the triangle is 75.06 sq cm
The domain of the equation are all the possible values of the independent variables that would make the equation reasonable, possible or true. In this item, the independent variable is r. This could take a value of 0 up to the point when m is equal to zero.
m = 30 - 3r = 0
r = 10
The domain is therefore [0, 10].
The range is the value of the dependent variable which would be from 0 to the point when no video game is played. This is, [0, 30].
The function is discrete because r and m cannot take every value in the number line.
X=-9
-x=9 so x=-9 since you inverse the sign
If you are working with time or days, you can't put in a negative value because if you are doing an experiment, you can't go back in time to do that experiment to gather data. (Time for the most part considered to be an input value so that's why I used it as an example.)
