Question

Use the image to answer the question.

A coordinate plane reveals a curve.
▼Click for Long Desc
The x-axis ranges from negative 4 to 4 in unit increments. The y-axis ranges from 0 to 2 in unit increments. The curve passes through the data points left parenthesis negative 4 comma 0 right parenthesis, left parenthesis 0 comma 1 right parenthesis, and left parenthesis 4 comma 1 point 4 right parenthesis. All values are approximate.

Rhianna graphed a square root function. What is the equation of the function she graphed?

(1 point)

y=2x+4−−−−−√


y=2x−4−−−−−√


y=12x+4−−−−−√


y=12x−4−−−−−√

Answer 1

y = (1/2)√(x + 4)

Reason: Let y = a√(x + 4) (it must start at x = −4 so the inside is x+4). At x = 0, 1 = a√4 = 2a, so a = 1/2. Check at x = 4: y = (1/2)√8 ≈ 1.414, matching the graph.