Sanjay needs 90 meters of fence to go around a rectangular garden.
The length l of the garden is three times its width w.

Three of these equations give the correct value for w.
Which equation does NOT?

Math item stem image
CLEAR CHECK

w+3w=90

w+3w+w+3w=90

2⋅w+2⋅3w=90

2⋅(3w+w)=90

2500

step-by-step explanation:

14.29%

step-by-step explanation:

let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3

then the equation is (x-x₁)(x-x₂) = 0

if you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.

step-by-step explanation:

you can see that a=1 (there is just an x²)

b = (-5 -2√7 + 2√7 - 5)/3 = -10/3

c = -2√7)/3 ) * (-5+2√7)/3) = -1/3

so your answer is 3x^2 – 10x – 1 = 0