Respuesta :

Answer:  45 degrees

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Work Shown:

We can apply the law of cosines

a^2 = b^2+c^2-2*b*c*cos(A)

(sqrt(5))^2 = (sqrt(2))^2+(3)^2-2*(sqrt(2))*(3)*cos(A)

5 = 2+9-6*(sqrt(2))*cos(A)

5 = 11-6*(sqrt(2))*cos(A)

11-6*(sqrt(2))*cos(A) = 5

-6*(sqrt(2))*cos(A) = 5-11

-6*(sqrt(2))*cos(A) = -6

(sqrt(2))*cos(A) = -6/(-6)

(sqrt(2))*cos(A) = 1

cos(A) = 1/(sqrt(2))

cos(A) = sqrt(2)/2

A = 45 degrees

Use the unit circle for the last step.

Interestingly, this triangle has only one angle that is a whole number. The other two angles are approximate decimal values.