To determine the number of cubes he needs to fill the box (this is assuming the cubes are 1 in cubes, he would need to calculate the volume of the box. To find the volume he would multiply the length by the width by the height. This would be 5 in x 6 in x 7 in. The volume is 210 cubic inches, so he could fill it with 210 one inch cubes.
It's a linear function. We need only two points to sketch the graph.
f(x) = -5x + 4 → y = -5x + 4
for x = 0 → y = -5(0) + 4 = 0 + 4 = 4 → (0, 4)
for x = 1 → y= -5(1) + 4 = -5 + 4 = -1 → (1, -1)
The domain and the range is the set of all real numbers.
-15 is already rational itself, but it as a fraction:
-15/1
2 (x+2)/(x-10) is the simplified answer