Answer: -13.9
This value is approximate.
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Step-by-step explanation:
This angle is in quadrant Q2, which is where x is negative and y is positive.
The angle shown of 65 degrees is added to the 90 degree angle to the right resulting in 65+90 = 155 degrees overall. See diagram below.
The x component of the vector is found by the formula
x = r*cos(theta)
we will plug in r = 15.3 as the magnitude of the vector and theta = 155 as the angle
x = 15.3*cos(155)
x = -13.8665 approximately
x = -13.9 rounding to one decimal place (as 15.3 and 65.0 are both rounded to one decimal place)