## YanaSidlinskiy one year ago @cj49

1. YanaSidlinskiy

$4x^2-17x-42=0$ Factor the left side:)

2. YanaSidlinskiy

It'd be something like: (4x+7)(x-6)?? I don't know if this is right...

3. UsukiDoll

expand (4x+7)(x-6) to see if it works...

4. YanaSidlinskiy

Not exactly sure if I'm targeting it right.. but 6?

5. UsukiDoll

|dw:1438776516354:dw| it works out

6. YanaSidlinskiy

Ok, then I probably stated the question wrong... The actual question is: The length of a rectangle is 17 centimeters less than four times its width. Its area is 42 square centimeters. Find the dimensions of the rectangle. Use the formula area=length*width

7. UsukiDoll

ah... that's what happened..

8. YanaSidlinskiy

Yeah sorry.

9. YanaSidlinskiy

It's ok. I'll figure it out somehow..

10. Nnesha

translate it into math equation The length of a rectangle is 17 centimeters less than four times its width. Its area is 42 square centimeters. |dw:1438776955499:dw| area = 22 now use that formula L times w =42 so two equations are L=4w-17 L times w =42 substitute L in 2nd equation for its value $\huge\rm w(\color{reD}{4w-17})=42$ you get 4w^2-14w-42 so when you factor it out you will get (4w-17)(w-6) now set both parentheses equal to 0 and then solve for w w-6=0 w= ?

11. Nnesha

so factor of 4w^2 -17 -42 is correct s UsukiDoll mentioned foil method to check if it correct or not

12. Nnesha

its*

13. YanaSidlinskiy

Thanks! I've got it figured out!