Part a.
In the first part of the problem we need to calculate the total area including the frame, for this, we use the formula for the area of a parallelogram:
In this case, the values of a, b and c are:
[tex]\begin{gathered} a=42\operatorname{cm} \\ b=65\operatorname{cm} \\ c=0.39m=39\operatorname{cm} \end{gathered}[/tex]
Thus, the area is:
[tex]\begin{gathered} A=65\operatorname{cm}\times39\operatorname{cm} \\ A=2,535\operatorname{cm}^2 \end{gathered}[/tex]
2,535 centimeters squared.
Part b.
In this part, we are asked to find the external perimeter of the picture frame.
For this, we use the formula to find the perimeter of a parallelogram:
Substituting the values of a and b from part a into the perimeter formula:
[tex]\begin{gathered} P=2(a+b) \\ P=2(42\operatorname{cm}+65\operatorname{cm}) \\ P=2(107\operatorname{cm}) \\ P=214\operatorname{cm} \end{gathered}[/tex]
The perimeter of the frame is 214 centimeters.
Answer:
A. Area
[tex]2,535\operatorname{cm}^2[/tex]
B. Perimeter
[tex]214\operatorname{cm}[/tex]
