H E L P !
The area of a rectangle is x2 - 2x - 15 and the length of the rectangle is x + 3. Find the width of the rectangle.

Question

H E L P !
The area of a rectangle is x2 - 2x - 15 and the length of the rectangle is x + 3.  Find the width of the rectangle.

erinweeks · Answer

answers 

	A. x – 5 	
	B. x2 + 15 	
	C. x + 5 	
	D. (x – 2)(x + 3)

valpey · Answer

Area           = Length * Width
$$x^2-2x-15 = (x+3)  * Width=(x+3)(x\pm ?)$$

erinweeks · Answer

do you know the answer or how to help more ?

erinweeks · Answer

????

anonymous · Answer

factor the left hand side of the equation

erinweeks · Answer

i dont know how to ..

anonymous · Answer

have you done it ever before? factoring trinomials?

anonymous · Answer

or you can do long division

erinweeks · Answer

not really , no !

erinweeks · Answer

i guessed i was D but it was wrong

valpey · Answer

$$x^2−2x−15=(x+3)∗Width=(x+3)(x+A)$$$$x^2−2x−15=(x*x)+ (x*A)+(3*x)+ (3*A)=x^2+Ax +3x+3A$$$$x^2−2x−15=x^2+Ax+3x+3A=x^2+(3+A)x+3A$$$$x^2−2x−15=x^2+(3+A)x+3A$$Solution where -2 = (3+A) and -15 = 3A