Here we are given the three sides of the triangle.
So we have Heron's formula to find its area.
Heron's formula is given by :

where A, B and C are sides of triangle and S is semi perimeter which is given by,

plugging values of A, B and C to find S

S=13.5
Now plugging values of A, B , C and S in Heron's formula

A=26.14 mm²
Answer: Area of triangle is 26.14 mm².
Answer:
hours
Step-by-step explanation:
Let x be the time ( in hours ) you feel good and y be the time ( in hours ) that you get tired.
As per given , we have
x+y= 8
Since : 
So , we have
20x+12y=122
According to the given question , we have the following system of equations ,

Multiply 12 on both sides of equation (1) , we get

Eliminate equation (3) from (2) , we get

Hence, you felt
hours good.
According to the fundemintal counting princable the answer is 18.
Answer: -13
Step-by-step explanation:
c-2y
= -5-2(4)
= -5 - 8
= -13