How do you solve for the unknown lengths and angle measures of triangle ABC where angle C = 90 degrees, angle B = 23 degrees and side a = 24?

3 Answers
May 5, 2018

# A=90^circ-B=67^circ #

#b = a tan B approx 10.19 #

# c = a/cos B approx 26.07 #

Explanation:

We have a right triangle, #a=24, C=90^circ, B=23^circ.#

The non-right angles in a right triangle are complementary,

# A=90^circ-23^circ=67^circ#

In a right triangle we have

# cos B = a/c #

# tan B = b/a#

so

#b = a tan B = 24 tan 23 approx 10.19 #

# c = = a/cos B = 24/cos 23 approx 26.07 #

May 5, 2018

Refer explanation.

Explanation:

Your question indicates unknown lengths which means you want to find length of #b# and #c# i assume.

Provided information : Angle B at #23# degrees // Length of #a# = #24# cm

To find length of #c#, use the provided info :

#sin (23) = c/24#

#:. c = 9.38cm# (Rounded off)

When #2# lengths are found, to find #b# apply Pythagoras Theorem

#sqrt (24^2 - 9.38^2)# = #22.09# cm (#b#)

To check if our values correspond to the angle given,

#tan^-1(9.28/22.09) = 23# degrees #sqrt#

Since triangle = #180# degrees, to find angle #A#,

#180 - 23 - 90 = 57# degrees

May 5, 2018

#angle A=67^@,b=10.187,c=26.072#

Explanation:

#:.180-(90+23)=67^@#

#:.(opposite)/(adjacent)=tan 23^@#

#:.opposite=adjacent xx tan 23^#

#:.opposite=24 xx tan 23#

#:.opposite=10.187=b#

Pythagoras:-

#:.c^2=a^2+b^2#

#:.c^2=24^2+10.187^2#

#:.c^2=576+103.775#

#:.c^2=679.775#

#:.sqrt(c^2)=sqrt(679.775)#

#:.c=26.072#