Question

Can some explain what To do

Answer 1

5 units.

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.

Answer 2

AB = 5

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;
`\angle A` and
`\angle C`) . That means that side AB equal side BC, then you can say:

`AB=BC\\3x-4=5x-10\\10-4=5x-3x\\6=2x\\3=x`

Now, if x=3, then using the formula for side AB they gave you:

`AB=3x-4=3(3)-4=9-4=5`