Me with this! very much appreciate

The answers for your two problems, can be found below in the attached images.

Problem 1

Graph

The graph was plotted using a calculator. We can see that the graph opens up.

f(x) = x^2 + 4x +3

Vertex

The vertex is the minimum point of the equation

In this case  Vertex (V) = (-2,-1)

Axis of symmetry

The x axis corresponding to the vertex component

x = -2

y intercept

Interception with the y-axis

From the first attached image, we can see that they y intercept occurs

at x = 0, y = 3  

(0,3)

Problem 2

Graph.

The graph was plotted using a calculator. We can see that the graph opens up.

f(x) = 2x^2 + 3x +1

Vertex

The vertex is the minimum point of the equation

In this case  Vertex (V) = (-0.75,-0.125)

Axis of symmetry

The x axis corresponding to the vertex component

x = -0.75

y intercept

Interception with the y-axis

From the second attached image, we can see that they y intercept occurs

at x = 0, y = 1  

(0,1)

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.