Question

What are the x-intercepts of the quadratic function? y = x2 – 3x + 2

A) 2 and 1
B) –2 and 1
C) 2 and –1
D) 1

Answer 1

y = x² - 3x + 2

The x-intercepts can be take by matching the equation to 0, so,

x² - 3x + 2 = 0

Δ = b² - 4.a.c

Δ = -3² - 4 . 1 . 2

Δ = 9 - 4. 1 . 2

Δ = 1

There 2 real roots.

x = (-b +- √Δ)/2a

x' = (--3 + √1)/2.1

x'' = (--3 - √1)/2.1

x' = 4 / 2

x'' = 2 / 2

x' = 2

x'' = 1

Alternative A.