A motorist travelled 60 km in 1 hour and a further 90 km in 2 hours. His average speed,
in km/hr, for the entire journey was​

the first one

step-by-step explanation:

just id the test.

it would be a on edgenuit y

the diagram below is your final answer

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

its a i did it myself

step-by-step explanation: