Given the trinomial, what is the value of the coefficient 'B' in the factored form?

2x2 + 14xy - 36y2 = 2(x + By)(x - 2y)

B= ____________

Question

Given the trinomial, what is the value of the coefficient 'B' in the factored form?

2x2 + 14xy - 36y2 = 2(x + By)(x - 2y)

B= ____________

tkhunny · Answer

Have you considered multiplying the binomials and seeing what you get?

anonymous · Answer

I don't know how and I'm really in a hurry to get this assignment done.  I have to be 80% complete with the course by Monday and Im only at 42%right now

anonymous · Answer

Can you explain how?

tkhunny · Answer

I don't believe you cannot multiply two binomials.  Give it a go.

(x + By)(x - 2y) = ??

anonymous · Answer

x^2+Bxy-2By^2.  Is that the correct answer?

tkhunny · Answer

You missed "-2xy"

anonymous · Answer

So x^2+Bxy-2xy-2By^2.  Is that better?

tkhunny · Answer

Okay, now somehow, 

2(x2 + 7xy - 18y2) =  2(x^2+Bxy-2xy-2By^2)

What value for B does that?

anonymous · Answer

@LearningIsAwesome

anonymous · Answer

@Sheraz12345

tkhunny · Answer

You didn't answ2er my question.  Look at the y^2 term.  What value for B makes those the same?

tkhunny · Answer

Considering ONLY the y^2 terms:

 - 18y^2 = -2By^2

What value of B will do that?

anonymous · Answer

2

tkhunny · Answer

Let's see, $-2(2) = -4 \ne -18$  You're just guessing.

$2B = 18$ - Solve for B.

anonymous · Answer

B=9?

tkhunny · Answer

Very good.  Do that again with the xy terms.

tkhunny · Answer

Well?

7xy = Bxy-2xy

What value of B will do that?