Alexis was making cupcakes for the town bake sale. She decorated 9 cupcakes in 30 minutes. If Alexis continued decorating cupcakes at
this rate, how many cupcakes would she decorate in 2 hours?
Johnny said that Alexis would be able to decorate 18 cupcakes in 2
hours. Is Johnny correct? If not, explain his mistake and identify the
correct solution.

Incorrect

Step-by-step explanation:

  because it takes 30 min to bake 9 which is half an hour, and if if you multiply 9 by 4 which 30 mins each it would be 36 cupcakes in 2 hours.

it will cost dollar $540

the living room is 3 which means if we divide 325/3 then we get $108

therefore if 1part of the living room cost $108 and 3 costed $325

then total 5part of the room will cost 5*108 which gives $540

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