Associate in a department store earns a commission on each suit and each pair of shoes sold. one week, she earned $47 in commission for selling 3 suits and a pair of shoes. the next week, she earned $107 in commission for selling 7 suits and 2 pairs of shoes. how much commission does she earn for selling each suit and each pair of shoes? solve by substitution.

the commission that she earns for selling each suit is $13

the commission that she earns for selling each pair of shoes is $8

Step-by-step explanation:

Let x represent the commission that she earns for selling each suit.

Let y represent the commission that she earns for selling each pair of shoes.

One week, she earned $47 in commission for selling 3 suits and a pair of shoes. It means that

3x + y = 47 - - - - - - - - - - 1

The next week, she earned $107 in commission for selling 7 suits and 2 pairs of shoes. It means that

7x + 2y = 107 - - - - -- - - - -2

Multiplying equation 1 by 2 and equation 2 by 1, it becomes

6x + 2y = 94

7x + 2y = 107

-x = -13

x = 13

Substituting x = -13 ,into equation 1, it becomes

3×13 + y = 47

39 +y = 47

y = 47 - 39 =

y = 8

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places