Question

What are the x– and y–intercepts of the quadratic equation y = (x – 1)^2 – 16?

Answer 1

y intercept is the value of y when x = 0
x intercept is the value of x when y = 0

y-intercept:

y = (0 - 1)^2 - 16
= (-1)^2 - 16
= 1 - 16
= -15

y-intercept: -15

x-intercept

y = (x – 1)^2 – 16

(x-1)^2 = y + 16
(x-1) = +/- sqrt(y + 16)

x = 1 +/- sqrt(y + 6)

x = 1 + sqrt(0 + 6) = 1 + sqrt(6)
and
x = 1 - sqrt(6)

x-intercepts: 1 + 6^(1/2) and 1 - 6^(1/2)

Ans. y-intercept = -15, x-intercepts = 1 + 6^(1/2) and 1 - 6^(1/2)