hmmm, between the three options I would go with the second one since the number of 1-foot cubes equals exactly the volume of the fish tank.
But to truly calculate the volume
5 x 3 = 15
15 x 3 = 45
45 is the volume of the fish tank
You may recall that you can't take the square root of a negative number (if you want a real number). So, the area under the square root, also known as the radicand, must be zero or positive. This is how we restrict the domain.
We write the inequality

.
B
8x + 7y = 19
- 8x
7y = 19 - 8x
÷ 7
y = 2 5/7 - 8/7x
So if that line is perpendicular to the line you're looking for, then the gradient (x value/slope) is the negative reciprocal to the gradient you're looking for, which would then be 7/8. You are told it has a y intercept of -7, so your final answer is:
y = -7/8x - 7
Hope this helps!
Hello!
First, let's write the problem.

Subtract 3x from both sides.


The opposite of division is multiplication, so we are going to multiply in order to undo the fraction.

Our final answer would be,

Thanks!
-TetraFish