PLEASE HELP! ABC is Isosceles what is AB?
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Answer:
AB = 5
Step-by-step explanation:
Since this is an isosceles triangle, you can conclude that there will be two sides of equal length and two angles of equal measurement.
The circular marks on Angle C and Angle A represent congruence between the two angles (The are the same measurement.). From this, you can also conclude that their opposite sides are congruent as well.
From this information you can set up your equation:
AB = BC
Substitute in the corresponding values to solve for x:
3x - 4 = 5x - 10
-2x = -6
x = 3
Substitute x into 3x - 4 to find the length of AB:
AB = 3(3) - 4
AB = 9 - 4
AB = 5