After being marked up 40%, the sale price of a tennis racket is $87.50 What was the original price of the tennis racket?

$62.50

Step-by-step explanation:

The original price is x

It is marked up 40 percent

x+.40x = new price

1.40x = new price

The new price is 87.50

1.40x = 87.50

Divide each side by 1.40

1.40x/1.40 = 87.50/1.40

x =62.50

The price before mark up is 62.50

$62.50

Step-by-step explanation:

After mark up, price is

100 + 40 = 140% of cost

140/100 × Cost = 87.50

Cost = 87.50 × 100/140

Cost = $62.50

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.