<span>2r ≤ 3(2r - 7)
</span><span>2r ≤ 6r - 21
</span><span>21 ≤ 6r - 2r
</span><span>21 ≤ 4r
</span><span>21/4 ≤ r
r</span>

21/4
r

5.25
You use the formula y=mx+b, therefore you have to isolate the y
First you subtract 3x to both sides.
3x - 5y = -35
-3x -3x
Then it would be
-5y = -3x -35
Then you divide -5 on both sides to isolate the y
-5y = -3x -35
/-5 /-5 /-5
Two negatives cancel out and make a positive so it would be
Y = 3/5x + 7
(:
X + x + x + x - 20 is equivalent to 4x - 20 because you can add the like terms, or the x's.
The volume is twice that of the cube of width, so the width of the original prism is
.. ∛(16 cm³/2) = 2 cm
Length = 4 cm
Width = 2 cm
Height = 2 cm