Question

Subtract b(b²+b-7)+5 from 3b²-8 and find the value of expression obtained for b= -3​

Answer 1

Answer:

the ans is 11

Step-by-step explanation:

subtract 8 from 19

Answer 2

Answer:

Question:

Subtract b(b² + b - 7) + 5 from 3b² - 8 and find the value of expression obtained for b = -3​.

What to find?

The difference of (3b² - 8) - (b(b² + b - 7)) and finding the value of expression    when b = -3.

Solution:

(3b² - 8) - (b(b² + b - 7))

After the removing the brackets in b(b² + b - 7),

(3b² - 8) - (b³ - b² + 7b)

After removing the brackets,

⇒ 3b² - 8 - b³ + b² - 7b

After rearranging the like terms,

⇒ -b³ + 3b² + b² - 7b - 8

After solving the like terms,

⇒ -b³ + 4b² - 7b - 8

After substituting the value for b = -3

⇒ -(-3)³ + 4(-3)² - 7(-3) - 8

After removing the brackets and solving the exponents,

⇒ 27 + 36 + 21 - 8

⇒ 76

∴ Thus the answer is 76.