Please help I will mark brainliest

a)(2x+1)² - 3

4x² + 4x + 1 - 3

4x² + 4x - 2

4(-2)² + 4(-2) - 2

16 - 8 - 2

6 (final answer)

b) 4(3)² + 4(3) - 2

36 + 12 - 2

46 ( final answer)

c) 2(x²-3) + 1

2x² - 6 + 1

2(3)² - 5

18 - 5

13(final answer)

answer: this is not a question

step-by-step explanation: this is a answer

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.