Question

If x = -1, what is the value of y in the equation?y = 8x3 + 12x2 - 6x - 3

8x3 means to the third exponent
And 12x2 means to the second exponent

Answer 1

The value of y is 7

Step-by-step explanation:

Since x= -1 , To find the value y in the equation replace x with -1 . Solve this equation using the order of operation PEMDAS. Before solving the problem, remember this in mind -1³= -1 × -1 × -1 = -1

-1 = -1 × -1 = 1

y = 8x³ + 12x² - 6x - 3

P(Exponent)MDAS solve the exponent

y = 8(-1)³ + 12(-1)² - 6(-1) - 3

y = 8(-1) + 12(1) - 6(-1) -3

PE(Multiplication)DAS , Multiply 8 and -1, 12 and 1, -6 and -1 .

y = -8 + 12 + 6 - 3

PEMD(Addition)S , Add -8,12 and 6

y = 10-3

PEMDA(Subtraction) , subtract 3 from 10

y = 7

The value of y in the equation y = 8x³ + 12x² - 6x - 3 is 7

Answer 2

Answer: y = 7

Work Shown:

`y = 8x^3 + 12x^2 - 6x - 3\\\\y = 8(-1)^3 + 12(-1)^2 - 6(-1) - 3\\\\y = 8(-1) + 12(1) - 6(-1) - 3\\\\y = -8 + 12 + 6 - 3\\\\y = 7\\\\`

Step-by-step explanation:

I replaced every x with -1. Then used the order of operations (PEMDAS) to simplify. Keep in mind that
`(-1)^2 = (-1)*(-1) = 1` and not
`(-1)^2 = -1`