Question

if x = -12 is the zero of the polynomial 8x3 -ax2 -x+2 find a

Answer 1

Step-by-step explanation:

x = -12 is the zero of the polynomial

$8x^3 - ax^2-x+2$

simply put the value of x in a given equation then we can get our answer, I. e a

$8x^3 - ax^2-x+2$

➡$8(-12)^3 - a(-12)^2-(-12)+2$

➡$(-1,728)(8)-a(144)+12+2$

➡$(-13,824)-144a+14$

➡$(-13,810)-144a$

➡$(-13810) = 144a$

$<strong>a = -95.906</strong>$

Verification :

$8(-12)^3 - (-95.90)(-12)^2-(-12)+2=0$

➡$(-13,810)-144(-95.906)$ = 0

➡$(-13,810)-144(-95.906)$ = 0

➡$(-13,810) + 13,810$ = 0

$0 = 0$

Answer 2

Answer:

Step-by-step explanation:

x = -12 is the zero of the polynomial

8x^3 - ax^2-x+28x3−ax2−x+2

simply put the value of x in a given equation then we can get our answer, I. e a

8x^3 - ax^2-x+28x3−ax2−x+2

➡8(-12)^3 - a(-12)^2-(-12)+28(−12)3−a(−12)2−(−12)+2

➡(-1,728)(8)-a(144)+12+2(−1,728)(8)−a(144)+12+2

➡(-13,824)-144a+14(−13,824)−144a+14

➡(-13,810)-144a(−13,810)−144a

➡(-13810) = 144a(−13810)=144a

a = -95.906a=−95.906

Verification :

8(-12)^3 - (-95.90)(-12)^2-(-12)+2=08(−12)3−(−95.90)(−12)2−(−12)+2=0

➡(-13,810)-144(-95.906)(−13,810)−144(−95.906) = 0

➡(-13,810)-144(-95.906)(−13,810)−144(−95.906) = 0

➡(-13,810) + 13,810(−13,810)+13,810 = 0

0 = 00=0