13.
а/8 = $1.25
Can someone help explain

a= $10.00

Step-by-step explanation:

It's very simple. Move /8 to the other side of the equation. It should give you $1.25 x 8. Solve the multiplication and you should get $10.00.

If I didn't make my explanation clear enough, please comment. I sometimes don't even explain myself very well.

a = 10

Step-by-step explanation:

a/8 = 1.25

multiply both sides by 8 to isolate a.

(8)(a/8) = 1.25(8)

which gives you

a = 1.25(8)

which simplifies to

a = 10

32/80  

91/140

the last one 54 doesn't go into 45. 54/100 ?

step-by-step explanation:

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