Can some explain what To do
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Answer:
AB = 5
Step-by-step explanation:
If the triangle is isosceles, then it has two equal sides, which must be facing the equal angles of the triangle (in our case the sides facing angles; [tex]\angle A[/tex] and [tex]\angle C[/tex]) . That means that side AB equal side BC, then you can say:
[tex]AB=BC\\3x-4=5x-10\\10-4=5x-3x\\6=2x\\3=x[/tex]
Now, if x=3, then using the formula for side AB they gave you:
[tex]AB=3x-4=3(3)-4=9-4=5[/tex]
Answer:
5 units.
Step-by-step explanation:
Because the triangle is isosceles the 2 sides opposite the equal angles are congruent.
AB = BC so:
3x - 4 = 5x - 10
10 - 4 = 5x - 3x
2x = 6
x = 3.
So the length of AB = 3(3) - 4 = 5 units.