Asked by VRE

hey i can't figure this one out, does anyone know the answer?

Question: Shenika factored the polynomial completely. What is the value of A?

5x3+35x2+6x+42

(5x2+A)(x+B)

A. 1
B. 5
C. 6
D. 7

(if anyone is confused why this question is written weird, i don't know why its like that either)

Answers

Answered by VRE
(and yes, im this bad at math)
Answered by mathhelper
Nothing at all wrong with this question, nor the way it is written

so you have:
(5x^2+A)(x+B) = 5x^3+35x^2+6x+42 , ..... notice how I wrote the powers.

expand the left side:
5x^3 + 5Bx^2 + Ax + AB

match the terms:
5x^3 <----> 5x^3
5Bx^2 <----> 35x^2 , so 5B = 35, then B = 7
Ax <----> 6x , then A = 6
AB <----> 42 , true since AB = 6*7 = 42

A = 6
B = 7 , so C is your correct choice

check, sub those values into the factored form,
(5x^2+6)(x+7)
= 5x^3 + 35x^2 + 6x + 42 , which is the expanded form given
So, my answer is correct
Answered by VRE
Ah thanks so much!

Related Questions