The questions are illustrations of Pythagoras theorem and trigonometry ratios.
<h3>What is Pythagoras theorem?</h3>
Pythagoras theorem is used to determine the lengths of the legs of a right triangle.
It is represented as:

Where:
b & c are the legs of the triangle, while a is the hypotenuse
<u>Question 16</u>
Start by calculating the value of x, using the sine ratio

Evaluate sin(30)

Solve for x


Next, calculate the length (l) of the boundary between both triangles using Pythagoras theorem


Collect like terms


Take the square root of both sides

Given that the angle is 45 degrees, it means that:

So, we have:



Divide through by 2

Take the square root of both sides

Hence, the values of x, y and z are:



<u>Question 18</u>
Start by calculating the value of z, using the sine ratio

Evaluate sin(45)

Solve for z


Next, calculate the value of y using tangent ratio

Solve for y

Evaluate tan(30)


Next, calculate the value of x using sine ratio

Solve for x

Evaluate sin(30)


Hence, the values of x, y and z are:



<u>Question 20</u>
Start by calculating the value of z, using the sine ratio

Evaluate sin(45)

Solve for z


Simplify

Next, calculate the value of y using tangent ratio

Solve for y

Evaluate tan(30)

Simplify


Next, calculate the value of x using sine ratio

Solve for x

Evaluate sin(30)


Hence, the values of x, y and z are:



Read more about Pythagoras theorem and trigonometry ratios at:
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