Answer:

Step-by-step explanation:
The graph you see there is called a parabola. The general equation for the graph is as below

To find the equation we need to find the constants a and b. The constant b is just how much we're lifting the parabola by. Notice it's lifted by 1 on the y axis.
To find a it's a little more tricky. Let's use the graph to find a value for a by plugging in values we know. We know that b is 1 from the previous step, and we know that when x=1, y=3. Let's use that!

Awesome, we've found both values. And we can write the result.

I'll include a plotted graph with our equation just so you can verify it is indeed the same.
Answer:
7
Step-by-step explanation:
When you match the form
... ax² + bx + c = 0
to the equation
... 3x² + 5x + 7 = 0
it is reasonable to conclude that ...
... a = 3, b = 5, c = 7.
_____
The question presumes you are familiar with the form
... ax² +bx +c = 0
which is often used as the representation of a general quadratic equation. This lets us use a, b, and c instead of specific numbers, to talk about ways of factoring, graphing, or solving equations like this.