Answer:
68-x
Step-by-step explanation:
71-x-3=71-3-x=68-x
For problems like this you can move the y's on the bottem up top by fliping the sign of the exponent (in this case 7 to -7) and MULTIPLYING it with EVERYTHING on top, then because of properties of multplication you can add the exponents to combine them into one term (in this case add 3 and -7 to get -4)

If any of this does not make sense let me know and ill try to clarify better
Add 70+93, then divide by the number of numbers, which is 2.
70+90=163
163/2=81.5
Hope this helps!
Answer:
C. AB = 5.8 cm
Step-by-step explanation:
In trapezoid ABCD, EF is the Midsegment.
.:. EF = {(AB+CD)
.:: 9.2 = {(AB + 12.6)
:: 9.2 x 2 = AB + 12.6
.. 18.4 = AB + 12.6
.. 18.4-12.6 = AB
:: AB = 5.8 cm
Take $15 and multiply it by 0.05 (this will get you the percent). You should get 0.75. So you add 0.75 to $15 and you should get $15.75