Question

A) Select the equation that has a y-intercept value of 3

A: y = (x + 1)(x – 3) B: y = x² – 9
C: y = 3x(x – 3)
D: y = (x + 1)(x + 3)

Answer 1

D

Explanation:

Given a quadratic in standard form

y = ax² + bx + c ( a ≠ 0 )

Then the y- intercept is the value of the constant term c

A

y = (x + 1)(x - 3)

= x² - 2x - 3 ← y- intercept = - 3

B

y = x² - 9 ← y- intercept = - 9

C

y = 3x(x - 3)

= 3x² - 9x ← y- intercept = 0

D

y = (x + 1)(x + 3)

= x² + 4x + 3 ← with y- intercept 3