An item has a listed price of $80. If the sales tax rate is 7%, how much is the sales tax (in dollars)

Multiplying a listed price by the percent can get you the sales tax, and then you can add.

(0.07 is 7% converted into a decimal)

So the item is $85.60 after sales tax.

You may also notice that multiplying the listed price by 1.07 will get you the same answer, without the need to add the sales tax.

Hope this helps.

頑張って!

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form