Answer:
18cm
Step-by-step explanation:
We have the length of the rectangle but we need to find the width which we'll call w. Area is a, l is length.
a = l * w
20 = 5 * w
divide both sides by 5 to cancel the multiplication by 5 on the right side
4 = w
The rectangle is going to have two sides that are the length of l, and two sides that are the the length of w. We're looking for the perimiter p.
p = 2l + 2w
p = (2 * 5) + (2 * 4)
p = 18
Answer:Area = 492.4 m²
Explanation:The area of the triangle can be calculated using the side-angle-side method as follows:
Area = 0.5 * first side * second side * sin(angle included between these two sides)
This rule is illustrated in the attached image.
Now, we have:
AB = 40 m
BC = 25 m
angle B which is the angle included between AB and BC = 80 degrees
The given angle is included between the two given sides, therefore, we can apply the above rule to get the area.
Area of triangle = 0.5*40*25*sin(80)
Area of triangle = 492.4 m²
Hope this helps :)
25 is the answer to your question