Four x plus two times two x minus one

Step-by-step explanation:

Four x: 4x

Two x: 2x

Two times two x: 2(2x) = 4x

Four x plus two times two x minus one: 4x + 2(2x) - 1 = 4x + 4x - 1

Combine like terms: = (4x + 4x) - 1 = 8x - 1

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15