6x - 15 = 90
6x = 90 + 15
6x = 105
x = 105/6
x = 17.5
Oh shucks, that's crazy man
Answer:
Hey there!
You could find the volume of the hole, and subtract it from the volume of the rectangular prism.
Hope this helps :)
First Step: Leave "x" alone, pass the 3 to the other side
X= 10+3
Second Step: Add 10 plus 3
X= 13
So your answer is: x=13