Answer:
Step-by-step explanation:
Notice that you are given an isosceles right-angle triangle to solve, since each of its two acute angles measures 
. Then such means that the sides opposite to these acute angles (the so called "legs" of this right angle triangle) must also be of the same length (x).
We can then use the Pythagorean theorem that relates the square of the hypotenuse to the addition of the squares of the triangles legs:
We use just the positive root, since we are looking for an actual length. then, the requested side is:
The length of side DE is 3cm
<h2 /><h3>Parallel line</h3>
Since the line AC is equivalent to DE, hence AC = DE
To get the length of DE, we will need to get the length oF AC using the Pythagoras theorem:
Given the following parameters
Hypotenuse = 5
Opposite = 4
Required
Adjacent side
Substitute the given parameters into the formula of Pythagoras theorem.
AC² = 5² - 4²
AC² = 25 - 16
AC² = 9
AC = 3
Hence the length of side DE is 3cm
Learn more on Pythagoras theorem here: brainly.com/question/12306722
Answer:
19,23
Step-by-step explanation:
9+x-7≥ 21
Combine like terms
2+x≥21
Subtract 2 from each side
2+x-2 ≥21-2
x≥19
Any number greater than or equal to 19
