Question

What is ​ BC ​?



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units

Answer 1

ABC is an isosceles triangle so AB = AC

Plug in

8x - 4 = 5x + 11

3x = 15

x = 5

BC = 4x - 2 = 4(5) - 2 = 20 - 2 = 18

Answer

BC = 18 units

Answer 2

Answer: BC = 18 units

Explanation:

In the given picture , we have ΔABC in which ∠B =∠C.

We know that the sides opposite to equal angles of a triangle are equal.

⇒ AB = AC (1)

Also, it is given that AB = 8x-4 , AC= 5x+11 and BC =4x-2

Substitute the value of AB and AC in equation (1) , we get

8x-4 = 5x+11

Subtract 5x from both sides , we get

3x-4=11

Now add 4 to both sides , we get

3x=15

Divide both sides by 3 , we get

x=5

Now, Substitute the value of x in BC , we get

BC= 4x-2 = 4(5)-2=20-2=18

Hence, BC = 18 units