i have two possible solutions for the angle A in the triangle A in the triangle ABC, it is either 136 or 44. the next question says given that A is an acute angle (and i know that B is an acute angle of 23 degrees, find the size of the angle A, giving your answer correct to the nearest degree..... i presume they want me to use the obtuse angle for C? but why? is there any rules about this?
thanks in advance :)
thanks in advance :)
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The only rule is that the sum of the angles must equal 180°. If two angles add to less than 90°, the third angle must be obtuse. If two angles add to more than 90°, the third angle must be acute.
If the two choices for angle A are 136° or 44°, and you are told that it's an acute angle, then angle A must be 44° since 44° is an acute angle (less than 90°) and 136° is an obtuse angle (greater than 90°)
If the two choices for angle A are 136° or 44°, and you are told that it's an acute angle, then angle A must be 44° since 44° is an acute angle (less than 90°) and 136° is an obtuse angle (greater than 90°)