Answer:
a)  p = 21.4 cm (nearest tenth)
B)  P = 45.6° (nearest tenth)
Step-by-step explanation:
As triangle PQR is a right triangle, we can use Pythagoras Theorem to find the length of p.
<u>Pythagoras Theorem </u>

where:
- a and b are the legs of the right triangle
 - c is the hypotenuse (longest side) of the right triangle
 
From inspection of the triangle:
- a = PQ = 21
 - b = QR = p
 - c = PR = 30
 
<u>Substitute</u> the given values into the formula and solve for p:






As p is the length, p can be positive only.
Therefore, p = 21.4 cm (nearest tenth)
To find the <u>angle P</u>, use the cosine trigonometric ratio.
<u>Cosine trigonometric ratio</u>

where:
 is the angle- A is the side adjacent the angle
 - H is the hypotenuse (the side opposite the right angle)
 
From inspection of the triangle:
 = P- A = PQ = 21
 - H = PR = 30
 
<u>Substitute</u> the given values into the formula and solve for P:



Therefore, the measure of angle P is 45.6° (nearest tenth).
Learn more about Pythagoras Theorem here:
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Learn more about trigonometric ratios here:
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