Answer:
Angle YZX = 19.7 degrees
This is the same as saying angle Z = 19.7 degrees
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Step-by-step explanation:
Since there are only three letters, and nothing else, we can refer to "angle YZX" as "angle Z" to shorten things. The middle letter is what determines the vertex of the angle.
With Z as the reference angle, side XY = 7.5 is the opposite side. It's the leg furthest from the reference angle. SIde ZY = 22.3 is the hypotenuse. The hypotenuse is always opposite the 90 degree angle.
We'll use the sine rule since it connects the opposite and hypotenuse
sin(angle) = opposite/hypotenuse
sin(Z) = XY/ZY
sin(Z) = 7.5/22.3
sin(Z) = 0.336323
Z = arcsin(0.336323)
Z = 19.653008983888
Z = 19.7
In this case, rounding to 3 sig figs means rounding to 1 decimal place (the first two digits are part of the whole number while the last digit is the decimal portion).
Make sure your calculator is in degree mode. The notation "arcsin" refers to arcsine which is the same as inverse sine. Your calculator would likely have the button
to indicate inverse sine.