Answer:
43
Step-by-step explanation:
if EF(part) = 18 and DF(the whole line) = 61
61-18 is 43. 43=DE
Please give brainliest thanks
Answer:

Step-by-step explanation:
Use a cofunction identity on the right hand side or left hand side...
So
.
We have the equation:

Make the above replacement:

Since cotangent has period 180 degrees, we can also write this as:

So solving the following will give us a set of solutions for
:

Add
on both sides:

Subtract 10 on both sides:

Divide both sides by 2:

Symmetric property:

Answer:
length = 24 meters
Step-by-step explanation:
1. l = 2w
2. P = 2l + 2w
P=72
3. 72 = 2l + 2w
4. Substitute w=l/2 to solve for l
72 = 2l + 2(l/2) ---> 72 = 3L - Divide by 3 on both sides
L= 24 meters
The area of a trapezoid can be found by the formula:
A = [(B + b) × h] / 2
where:
B = major base = 36 in
b = minor base = 30 in
h = height = 24 in
Therefore, with the given data you can calculate the area by applying the formula:
<span>A = [(36 + 30) × 24] / 2
= [66 </span><span>× 24] / 2
= 792 in</span>²
Hence, the area of the trapezoid is 792 in<span>².</span>