The estimated total cost, y, of a child’s toy is partially based on the number of batteries used, x. The cost of one battery is $0.75. The toy itself costs $12. Which equation represents the situation? y = 12x + 0.75
y = 0.75x + 12
y = 12x – 0.75
y = 0.75x – 12

Step-by-step explanation:

if the cost of a battery is 0.75$ and is represented by x, then 0.75 is x's coefficient.

now, you add the cost of the toy, 12$ to the cost of the batteries,

creating an equation

y=0.75x+12, which is option B

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