In △ABC, AB = BC = 20 and DE ≈ 9.28. Approximate BD.

BD = 5

Step-by-step explanation:

∠A = 60°

Since AB = 20 = BC, Then ∠B = 60° resulting in a equilateral triangle with ∠C = 60°.  Then dividing ∠DAE into half gives 4 = angles of 15° yielding each secition of BC being equal to 20/4 = 5.  Do i don't think DE ≈ 9.28 cannot occur.

answer: standard form is ax^2 + bx + c = 0

step-by-step explanation:

standard form is ax^2 + bx + c = 0

(2x + 1)(x - 2) = 0

distribute to get into standard form

2x^2 - 4x + x - 2 = 0

2x^2 - 3x - 2 = 0

a = 2, b= -3, c = -2

a is your answer

expression #3 is not equivalent. the others are.