A would be the correct ans
For the sake of showing work I will replace the empty space with an x like so...

To find out what x is you must cross multiply (aka butterfly)
***Image of this step is attached below
9*x = 10*90
9x = 900
Next divide 9 to both sides to finish isolating x. Since 9 is being multiplied by x, division (the opposite of multiplication) will cancel 9 out (in this case it will make 9 one) from the left side and bring it over to the right side.
9x ÷ 9 = 900 ÷ 9
1x = 100
x = 100
To make these fractions equivalent the empty spot must be 100

Hope this helped!
~Just a girl in love with Shawn Mendes
Answer:
<h2>1005.12</h2>
Step-by-step explanation:
<u>first</u><u> </u><u>we </u><u>need</u><u> to</u><u> </u><u>know</u><u> that</u><u> </u><u>r</u><u>edious</u><u> </u><u>isn't</u><u> </u><u>gien</u>
so we have to find redious
according to Pythagoras theorem
a²+b²=c²
a=√c²-b²
a=17²-15²
a=√(17+15)(17-15)
a=√64
a=8







<h3>
Answer: 20% discount</h3>
Work Shown:
amount saved = 84-67.20 = 16.80 dollars
Divide this over the original larger price to get 16.80/84 = 0.20 = 20%
Note how 20% of 84 = 0.20*84 = 16.80 to help check the answer.
Or we can say 0.80*84 = 67.20 which also helps confirm the answer.
The 0.80 is from the fact that you save 20% but still have to pay the remaining 80%
Its C. i put my best guess into it even tho i kinda suck at geometry <span />