Answer:
Perimeter is 17.07
Step-by-step explanation:
We know that DF = EF = 5 cm, since D and E are the midpoints of AC and AB, both of which are 10 cm in length.
We need to use the Pythagorean theorem to get the length of DE.
So the perimeter of DEF is 5 + 5 + 7.07 = 17.07
Answer:
A = 10.27cm²
Step-by-step explanation:
Let's represent the width as x,
therefore since the length is 4 more than 3 times the width, it can be represent as 3x + 4, Perimeter = 18.4cm
Perimeter of a rectangle = 2(L + B)
width = 1.3cm
Length = 3x + 4 = 3*1.3 + 4 = 7.9cm
Area of a rectangle = length x width
A = 7.9 * 1.3 = 10.27cm²