Which equation could solved using the graph above

Notice all the important features of the graph, 

1) The graph is a parabola; 
2) Roots are -2, -1 
3) A point is (-3, 2) 

Put all this information into an equation;

y=a(x-r)(x-s) 
y=a(x+1)(x+2) <-- signs revered due to the negative sign 
2=a(-3+1)(-3+2) <-- put in the values of x and y to find a
2=a(-2)(-1) 
2=a(2)
2/2=a
1=a 

y=(x+2)(x+1) <-- find in standard form by expanding 
y= x²+x+2x+2 
y=x²+3x+2 

Therefore, the correct option is the second one;

Hope I helped :) 

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

1 the 1st term, 3 the 2nd term, 6 the 3rd term,etc.

note the following:

from the 1st term (1) to the 2nd term (3), we go up by 2,from the 2nd term (3) to the 3rd term (6), we go up by 3from the 3rd term (6) to the 4th term (10), we go up by 4, andfrom the 4th term (10) to the 5th term (15), we go up by 5.

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

If gravity is one third on mars then weight also one third on mars