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:
Value of x is used to consider unknown value. The letter “x” is commonly used in algebra to indicate an unknown value. It is referred to as a “variable” or, in some cases, a “unknown.” In x + 2 = 7, x is a variable. ... A variable need not be “x,” but might be “y,” "w," or any other letter, name, or symbol.
-56
Explain 9x7 is 56 then you add a negative. Please thanks and brainliest if correct!