Question

Copy and complete the table of

values for
y=-3x³
2x² + 4x + 5.
What numbers
replace A, B and C?
1 2
C
X
-2 −1
-1
Y A 2
0
5 B

Answer 1

y = -3x³ - 2x² + 4x + 5

x -2 -1 0 1 2

y 13 2 5 4 -19

Explanation:

-3(-2)³ - 2(-2)² + 4(-2) + 5 =

-3(-8) - 2(4) - 8 + 5 =

24 - 8 - 8 + 5 = 13

-3(1³) - 2(1²) + 4(1) + 5 =

-3 - 2 + 4 + 5 = 4

-3(2³) - 2(2²) + 4(2) + 5 =

-3(8) - 2(4) + 8 + 5 =

-24 - 8 + 8 + 5 = -19

Answer 2

A = 13, B = 4, C = -19

Explanation:

Equation: y = -3x^3 - 2x^2 + 4x + 5

Simplify substitute the values:

• when x = -2,

y = -3(-2)^3 - 2(-2)^2 + 4(-2) + 5 = 13

• when x = 1,

y = -3(1)^3 - 2(1)^2 + 4(1) + 5 = 4

• when x = 2,

y = -3(2)^3 - 2(2)^2 + 4(2) + 5 = -19