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5 votes
Why did I get it wrong ? I’m finding constant B and idk what’s wrong with my step.

Why did I get it wrong ? I’m finding constant B and idk what’s wrong with my step-example-1
User Nick Yap
by
4.0k points

2 Answers

5 votes

Answer:

B = -13

Explanation:

Nothing is wrong you just have to complete it..

soo continuing from where you stopped.

Ax² - 2Ax - 3x + 6 = 5x² + Bx + 6

(its supposed to be the equivalence sign [with three dashes] but I am restricted by my keypad, so I made use of the equal to sign [two dashes])

comparing both sides, we can therefore say:

Ax² = 5x²..............i

- 2Ax - 3x = Bx......ii

+6 = +6..............iii

sub the value of A = 5 into ......ii

-2Ax - 3x = Bx

-2(5)x - 3x = Bx

-10x - 3x = Bx

-13x = Bx

B = - 13

User Simomo
by
4.6k points
4 votes

Answer:


\large \boxed{\sf \ \ A=5, \ \ B=-13 \ \ }

Explanation:

Hello,

What you did is correct...


(Ax-3)(x-2)=5x^2+Bx+6\\\\\text{*** we develop the left side ***}\\\\Ax^2+(-2A-3)x+6=5x^2+Bx+6

... and you found A by identifying the term in
x^2 to get A = 5, right?

What about the other terms?

We can then identify the like terms:

>>> term in
x^2\\

A = 5

>>> term in x

-2A+3=B

>>> constant term

6 = 6

As we know that A=5 it means that B = -2*5-3=-13

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

User Camilo Terevinto
by
3.7k points