Janice bought three lamps for her new apartment in a city where the sales tax rate is 5%. the lamps cost $25, $35, and $45. find the total cost of her lamp purchase , including sales tax.

Remark

You could do this by taking 5% of each lamp as

5% *25 + 25

5%* 35 + 35

5%*45 + 45

The easier way is to pretend that she bought all three at the same place at the same time.

(25 + 35 + 45)*(5/100) + 105

Easier yet is to do it this way.

(35 + 25 + 45)*1.05 = 105 * 1.05 = 110.25

because its not ur topic and its not for is for homework not that.

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