A pair of jeans costs $25.00 , and the sales tax is 5 percent of the price whats the sales tax and the total of the jeans

26.25$

Step-by-step explanation:

25

%

o

f

40

=

25

100

×

40

=

10

 discount

price =

40

−

10

=

$

30

Second method. Find 75% immediately

75

%

o

f

40

=

75

100

×

40

=

$

30

You can do any percentage question using the concept of direct proportion.

40

100

=

x

75

                     if $40 is 100%, how much is 75%?

100

x

=

75

×

40

                           cross-multiply

x

=

75

×

40

100

 this a possible expression for the sale price

x

=

$

30

Step-by-step explanation:

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