evaluate the expressions?

2 ⤊

first one : x^3 when x=4
second : 2x^3-21 when x=5

2007-01-24 10:27:29 · 3 answers · asked by bonjour 1 in Education & Reference ➔ Homework Help

1) (4)^3 = 4 times 4 times 4 = 64

2) 2(5)^3 - 21
= 2(125) - 21
= 250 - 21
= 229

2007-01-24 10:31:54 · answer #1 · answered by MsMath 7 · 2⤊ 0⤋

x^3 = x * x * x = 4 * 4 * 4 = 64

2x^3-21 = 2 * (x*x*x) - 21 = 2 * (5*5*5) - 21

2007-01-24 18:33:27 · answer #2 · answered by sadfwer 3 · 0⤊ 0⤋

time to go lay down....maths always makes me like this.

2007-01-24 18:32:22 · answer #3 · answered by Anonymous · 0⤊ 0⤋