Given the quadratic function, to get the roots we factorize:
3x²-4x-7=0
3x²+3x-7x-7=0
3x(x+1)-7(x+1)=0
(3x-7)(x+1)=0
thus the roots are
x=-1 or x=3/7
thus the sum of the roots will be:
-1+3/7
=-4/7
It's the first one. Note that for each unit increase in x, y increases by 1/2:
outputs are 1/2, 2/2, 3/2, 4/2, corresponding to 1, 2, 3 and 4 as inputs.
1) is 1 2) 2 is 8.60 4 is 10.00 5 is 24.00