Question

(SAT prep) In △ABC, AB = BC =20, DE ≈ 9.28. Approximate BD.

Answer 1

Answer: BD = 5.36 ≈ 5.4

Explanation:

length of line AB = length of line BC = 20, line DE ≈ 9.28

Since the length of line AB and line BC are equal, it follows that the length of line BD and line EC are also equal. Therefore, to get the length of line BD will be the difference between the length of lines BC and DE; the result is then divided by 2. The result gives us the length of line BD or line EC because the length of lines BD and EC are equal [BD = EC]

Mathematically,

BD =
`(BC - DE)/(2)` =
`(20 - 9.28)/(2)` =
`(10.72)/(2)`

BD = 5.36 ≈ 5.4