Answer:
Step-by-step explanation:
The sum of angles in a triangle is 180°. In an isosceles triangle, the base angles are congruent.
For this, it is easiest to find the base angles first. If we let <em>b</em> represent the measure of one of them, the sum of angles is ...
2b +42 = 180
b +21 = 90 . . . . . . divide by 2
b = 69 . . . . . . . subtract 21
The measure of the base angles is 69°.
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Then we can find the value of x from its relation to the base angle measure:
(2x +3)° = 69°
2x = 66 . . . . . . . . . divide by °, subtract 3
x = 33 . . . . . . . . divide by 2
The value of x is 33.
